CN103562893A - Facilitating transport mode input/output operations between a channel subsystem and input/output devices - Google Patents

Abstract

A computer program product is configured for performing a method including: generating at least one command message by a channel subsystem of the host computer system, the at least one command message including one or more device command words (DCWs), wherein at least one DCW of the one or more DCWs includes a suppress-length indication (SLI) configured to instruct a control unit to continue to perform the I/O operation in response to the control unit detecting that the data count does not match an amount of data required; receiving an incorrect length (IL) value, the IL value being a first IL value in response to the SLI being a first SLI value and the data count not matching the amount of data required; and responsive to receiving the IL value from the control unit, storing an IL indicator in a subchannel-status word.

Description

Promote the transmission mode input/output operations between channel subsystem and input-output apparatus

Technical field

Relate generally to I/O of the present invention (I/O) is processed.More particularly, the present invention relates to provide the feature that promotes transmission mode I/O operation.

Background technology

I/O (I/O) for transmitting data between storer and the I/O equipment of I/O disposal system.Particularly, by carrying out I/O, operate, data are write to one or more I/O equipment from storer, and data are read to storer from one or more I/O equipment.

In order to promote the processing of I/O operation, adopt the I/O subsystem of I/O disposal system.I/O subsystem is connected to the I/O equipment of primary memory and I/O disposal system, and guidance information flows between storer and I/O equipment.An example of I/O subsystem is channel subsystem.Channel subsystem is used channel path as communication media.Each channel path comprises the passage being connected with control module, and this control module is further connected to one or more I/O equipment.

Channel subsystem and I/O equipment can be in executable operations under transmission mode, and this pattern support is transmitted one or more command control blocks to transmit data between I/O equipment and storer.Transmission control word (TCW) is specified the one or more I/O orders that will carry out.For the order of initiating specific I/O operation, TCW specify with the storage area of operative association, complete and this region between the afterwards performed operation of transmission, and other selection.

Summary of the invention

Embodiment comprises a kind of for computer program, described control module and one or more devices communicating being configured to carry out on the host computer system of communicating by letter with control module the I/O operation that I/O (I/O) operational order initiates.Described computer program comprises tangible storage medium, it can read and store the instruction of being carried out a kind of method by described treatment circuit by processed circuit, described method comprises: the command messages that produces at least one assigned I/O operation by the channel subsystem of described host computer system, described at least one command messages comprises one or more unit command words (DCW), each DCW and I/O order association, at least one DCW in wherein said one or more DCW comprises data counts and suppresses Length Indication (SLI), whether described SLI is configured to indicate described control module to continue in response to described control module detects incorrect length condition, to continue to carry out described I/O operation, described incorrect length conditional response does not mate and is detected in the described data counts data volume required with carrying out described I/O operational order, wherein required data be on described control module, can be used for the data of read operation order and described control module need to be for one of data of write operation order, described at least one command messages is forwarded to described control module, from described control module, receive incorrect length (IL) value, in response to described SLI, be that a SLI value and described data counts do not mate with required data volume, described IL value is an IL value, in response to described SLI, be that the 2nd SLI value and described data counts do not mate with required data volume, described IL value is the 2nd IL value, and in response to receive described IL value from described control module, IL indicator is stored in subchannel status word, described IL indicator represents described IL value.

Another embodiment comprises a kind of for device, described control module and one or more devices communicating being configured to carry out on the host computer system of communicating by letter with control module the I/O operation that I/O (I/O) operational order initiates.Described host computer system is configured to carry out: the command messages that produces at least one assigned I/O operation by the channel subsystem of described host computer system, described at least one command messages comprises one or more unit command words (DCW), each DCW and I/O order association, at least one DCW in wherein said one or more DCW comprises data counts and suppresses Length Indication (SLI), whether described SLI is configured to indicate described control module to continue in response to described control module detects incorrect length condition, to continue to carry out described I/O operation, described incorrect length conditional response does not mate and is detected in the described data counts data volume required with carrying out described I/O operational order, wherein required data be on described control module, can be used for the data of read operation order and described control module need to be for one of data of write operation order, described at least one command messages is forwarded to described control module, from described control module, receive incorrect length (IL) value, in response to described SLI, be that a SLI value and described data counts do not mate with required data volume, described IL value is an IL value, in response to described SLI, be that the 2nd SLI value and described data counts do not mate with required data volume, described IL value is the 2nd IL value, and in response to receive described IL value from described control module, IL indicator is stored in subchannel status word, described IL indicator represents described IL value.

Another embodiment comprises a kind of for method, described control module and one or more devices communicating being configured to carry out on the host computer system of communicating by letter with control module the I/O operation that I/O (I/O) operational order initiates.Described method comprises: the command messages that produces at least one assigned I/O operation by the channel subsystem of described host computer system, described at least one command messages comprises one or more unit command words (DCW), each DCW and I/O order association, at least one DCW in wherein said one or more DCW comprises data counts and suppresses Length Indication (SLI), whether described SLI is configured to indicate described control module to continue in response to described control module detects incorrect length condition, to continue to carry out described I/O operation, described incorrect length conditional response does not mate and is detected in the described data counts data volume required with carrying out described I/O operational order, wherein required data be on described control module, can be used for the data of read operation order and described control module need to be for one of data of write operation order, described at least one command messages is forwarded to described control module, from described control module, receive incorrect length (IL) value, in response to described SLI, be that a SLI value and described data counts do not mate with required data volume, described IL value is an IL value, in response to described SLI, be that the 2nd SLI value and described data counts do not mate with required data volume, described IL value is the 2nd IL value, and in response to receive described IL value from described control module, IL indicator is stored in subchannel status word, described IL indicator represents described IL value.

By the technology of this embodiment, can realize further feature and advantage.Other embodiment and aspect are in this description and a part of the present invention of stating in being regarded as claim.In order to understand better advantages and features of the invention, consult now and describe and accompanying drawing.

Accompanying drawing explanation

Be regarded as theme of the present invention and in the claim of instructions ending place, point out specially also explicit state.When detailed description below reading by reference to the accompanying drawings, above-mentioned and other target, feature and advantage of the present invention will become apparent, in these accompanying drawings:

Fig. 1 illustrates an embodiment of the I/O disposal system of integrated and use one or more aspects of the present invention;

Fig. 2 illustrates an embodiment of transmission control word (TCW);

Fig. 3 illustrates an embodiment of transmission command controll block (TCCB);

Fig. 4 illustrates an embodiment of the transmission command message unit (IU) of the TCCB comprising in Fig. 3;

Fig. 5 illustrates an embodiment of the transmission command head of the transmission command IU in Fig. 4;

Fig. 6 illustrates an embodiment of the transmission command region head (TCAH) of the TCCB in Fig. 4;

Fig. 7 illustrates an embodiment in the transmission command region (TCA) of the TCCB in Fig. 4;

Fig. 8 is that explanation is for exemplary definite table of the various data counts of one-way data transmission operation;

Fig. 9 is that explanation is for exemplary definite table of the various data counts of bidirectional data transfers operation;

Figure 10 illustrates an embodiment of unit command word (DCW);

Figure 11 illustrates an embodiment of the control attribute field of the DCW in Figure 10;

Figure 12 illustrates exemplary command code and the sign of DCW;

Figure 13 illustrates an embodiment of transmission command area extension (TCAX);

Figure 14 illustrates an embodiment of CBC offset blocks;

Figure 15 illustrates for carrying out the process flow diagram of embodiment of the method for transmission mode I/O operation;

Figure 16 illustrates for transmit the embodiment of the transmission data I U of input and output data between passage and control module and/or I/O equipment;

Figure 17 illustrates the n embodiment of the interrupt response piece (IRB) that comprises subchannel status word (SCSW);

Figure 18 A and 18B illustrate the exemplary status qualifier of the SCSW in Figure 17;

Figure 19 illustrates an embodiment of transmission response IU; And

Figure 20 illustrates an embodiment of the state region of the transmission response IU in Figure 19.

Embodiment

Embodiments of the invention promote the I/O (I/O) in computer system to process.In one embodiment, provide transmission command with managing I/O operation and transmit data by channel path.Transmission command transmission is for the order metamessage (TCMI) of management data transfer check and other DCW transmission.The transmission control word (TCW) that TCMI can define in one or more data transmission information unit (IU) is specified, and this transmission massage unit is for defining, specify and verify the information of the relevant data that will transmit in I/O operation.Transmission command can comprise inquiry command, transmission CBC offset blocks (TCOB) order, and transmission TCA expansion (TTE) order.

In one embodiment, I/O processes by making principal computer increase can send to equipment and promotes to carry out the command number of I/O operation.For example, take transmission command area extension (TCAX) form TCMI can from main frame send to equipment with increase can with the command number of I/O operative association.In one embodiment, TCAX can be specified and be passed through unit command word (DCW) by TCW and send, and this DCW is called as transmission TCA expansion (TTE) DCW, comprises the order except sending in transmission command region (TCA), needs in addition the order of carrying out.In one embodiment, TCAX is specified by TTEDCW and sends to control module as output data.

I/O also processes can be by providing a kind of device to promote, by this device, I/O equipment can continue I/O operation running into when incorrect length records.For example, DCW incorrect length and FCX incorrect length deixis can be installed in main system and control module or equipment.This function provides the incorrect length (IL) of can controlled unit carrying out to check.Can in being sent to the DCW of equipment, add and suppress incorrect length or suppress Length Indication (SLI) field.When activating this, allow DCW chain to continue when control module detects incorrect length condition.

I/O processes also can be by providing a kind of device to promote, this device, for operating by single I/O, will read and write order simultaneously and send to equipment.Prior art TCW channel program is specified all order or all reading orders of writing.Bidirectional operation can be specified by setting one or more signs in the transmission command head (TCH) at order IU, for example, by reading and write, indicates and is made as 1, and provide to read with data writing simultaneously and count.In addition, the initiation such as process login (PRLI) request message or the sign in log messages can be set as indication channel subsystem and support bidirectional data transfers.Response message such as PRLI accepts message can comprise can be set as the sign whether indicating equipment supports bidirectional data transfers.If main frame and control module are all supported bidirectional data transfers, but read and write sign, in order IU, set, equipment can reporting errors.This function is the improvement of prior art fiber channel protocol, and fiber channel protocol is not supported bidirectional data transfers operation.As described in this, " bidirectional data transfers " is in single TCW I/O operation, to carry out the transmission of input and output data simultaneously, for example, sends and order is read and write in execution in single TCW I/O operates simultaneously.

Fig. 1 illustrates the exemplary embodiment of I/O disposal system 100, and this disposal system comprises the host computer system 102 that contains data storage device and/or disposal system, for example International Business Machine Corporation (IBM) (

) release mainframe computer.IBM is the registered trademark that is positioned at the International Business Machine Corporation (IBM) of USA New York A Mengke.Registered trademark, trade mark or name of product that other title used herein may be International Business Machine Corporation (IBM) or other company.Host computer system 102 comprises various processing, storage and communication device.In one embodiment, host computer system 102 comprises one or more CPU (central processing unit) (CPU) 104, the storer such as main storage means or storer 106, extension storage device or storer 108, one or more operating systems (OS) 110 of being carried out by one or more CPU104.For example, a CPU104 can carry out

operating system 110 and/or

operating system 110 is as different virtual machine instance.CPU104 is the control center of I/O disposal system 100.It comprises serializing and processing capacity for instruction execution, interrupt operation, timing function, initial program loading and other machine correlation function.CPU104 is connected to primary memory 106 and/or extended memory 108 by the connection 113 such as two-way or unidirectional bus.

Host computer system 102 also comprises channel subsystem 114, and this subchannel system provides the communication interface between main system 101 and various I/O equipment 116, and it can be controlled by one or more control modules 118.I/O equipment comprises the equipment such as printer, magnetic tape unit, DASD, display, keyboard, communication controler, teleprocessing equipment and sensor-based equipment.In description herein, term " control module " and " equipment " can be used interchangeably, or control module can be regarded as comprising one or more equipment.Channel subsystem 114 is guidance information stream between I/O equipment 116 and host computer system 102.It makes CPU104 from the task of directly communicating by letter with I/O equipment 116, remove out and allow data processing and I/O processing to carry out concurrently.Channel subsystem 114 is connected to CPU104, primary memory 106 and/or extended memory 108 by the connection 120 such as bus.

In one embodiment, channel subsystem 114 is connected to each I/O equipment 116 by each " channel path " 122, and these channel paths are connected to each control module 118 by the connection 124 such as serial or parallel link by channel subsystem 114.Control module 118 can be connected to communication subsystem 114 by more than one channel path 122, and I/O equipment 116 can be connected to more than one control module 118 and/or I/O equipment 116.In a word, independent I/O equipment 116 can be accessed by a plurality of channel paths simultaneously.Channel path can be used various types of connections, for example parallel interface, serial i/O interface and FICON I/O interface.For example, serial-port path can comprise one or more optical fiber, and these optical fiber are connected to control module 118 by the dynamic switch 126 in Fibre passage optical fiber for example, and parallel interface can comprise a plurality of electric conductors or conductor fiber.

In one embodiment, channel subsystem 114 comprises one or more independent passages 128, and they are connected to one or more control modules 118 and/or I/O equipment 116 by one or more channel paths 122 respectively.Each passage 128 comprises processing electronic component, for example local channel microprocessor 130 and be connected to local channel microprocessor 130 and can be by the local channel storer 132 of local channel microprocessor 130 access.Local channel storer 132 can comprise the information such as channel program appointment, channel path identifier, device number, unit count, state indication, and about the information of route availability and pending or the function carried out.

In each passage 128, also comprise one or more subchannels in addition.Each subchannel is the data structure that is positioned at channel memory 132, they provide about associated I/O equipment 116 and with the information being connected of channel subsystem 114.The information that subchannel also provides relevant I/O operation and relates to other function of associated I/O equipment 116.Subchannel is a kind of device, and by this device, channel subsystem 114 offers CPU104 by the information of relevant associated I/O equipment 116.The quantity of the subchannel that in one or more embodiments, channel subsystem provides is independent of the quantity of the channel path 122 of associated I/O equipment 116.For example, the equipment 116 that can access by the channel path 122 replacing is still represented by single subchannel.

Each control module 118 provides operation and controls the logic of one or more I/O equipment 116, and the LI(link interface) of using general utility functions that the characteristic adaptation passage 128 of each I/O equipment 116 is provided.The execution of I/O operation is provided these general utility functionss, the indication of the state of relevant I/O equipment 116 and control module 118, the control regularly of the data transmission on channel path 122, and other I/O equipment control of a specific order.Control module 118 can encapsulate separately, also can be physically and logically integrated with I/O equipment, channel subsystem or CPU.

One or more said modules of I/O disposal system 100 further "

z/Architecture Principles of Operation( z/Architecture principle of operation, publication number is SA22-7832-08, in August, 2010, the 9th edition) " in be described.

I/O operation is described to relate to any operation of the data transmission between host computer system and I/O equipment 116.As described here, I/O operation comprises communicating by letter (in one embodiment between channel subsystem 114 and equipment 116, by control module 118), wherein individual command (for example, channel command word or CCW), the individual command message that comprises a plurality of orders (for example, transmission command message unit or transmission command controll block (TCCB)) or multichain order (for example, a plurality of CCW) from channel subsystem 114, send to equipment.I/O operation can also comprise that equipment 166 or associated control module 118 are in response to receiving and/or fill order or chain order and one or more response messages of producing.

In one embodiment, I/O operation is initiated by carrying out the I/O instruction of OS110 generation by equipment 116, the subchannel that these instruction appointments are associated with equipment 116.This type of instruction is carried out by CPU104 in main system, and concrete mode is that CPU104 sends to passage 128 by parameter or subchannel is carried out the various functions in I/O operation with request channel subsystem 114.

For example, CPU104 carries out " STARTSUBCHANNEL " instruction with request channel subsystem 114 by the I/O equipment associated with subchannel 116 execution start-up performances by parameter being sent to target subchannel.Channel subsystem 114 is by using the information (comprising the information of transmitting when carrying out START SUBCHANNEL instruction) on subchannel to search the addressable channel path of equipment 116, and the I/O carrying out after selected channel path operates to carry out start-up performance.

When the instruction such as START SUBCHANNEL is carried out by CPU104, passage 128 starts to carry out I/O operation.In one embodiment, channel subsystem 114 is according to high-performance FICON(HPF) agreement executable operations, this agreement is for communicating by letter between channel subsystem 114 and equipment 116 and/or control module 118.FICON and HPF are further described in " Fibre Channel:Single-Byte Command Code Sets Mapping Protocol – 4 (FC-SB-4) (optical-fibre channel: byte command code sets shadowing agreement-4 (FC-SB-4); T11Project2122-D; on September 22nd, 2009, revised edition 3.00) ".

In one embodiment, the execution of START SUBCHANNEL instruction by the delivery of content of operation request block (ORB) to channel subsystem 114.ORB specifies the channel program of the address that comprises one or more command words (channel command word for example, further describing or transmission command word) below.There are two seed channel operation patterns.In one embodiment, host computer system 102 executable operations under command mode is also specified the command word of taking channel command word (CCW) form.In another embodiment, main system executable operations under transmission mode is also specified the command word of taking transmission command word (TCW) form.

When the expansion of FCX(optical-fibre channel is installed) function, and as the result of carrying out the START SUBCHANNE instruction of specifying TCW channel program, while setting start-up performance on subchannel, subchannel can enter transmission mode.Subchannel remains under transmission mode, until the start-up performance of resetting on subchannel, on other is free, subchannel is under command mode.

Under command mode, passage is carried out CCW channel program, and this channel program comprises single channel command word or the series of passages command word of carrying out in order, the particular order of these channel command word control channel operations.Control module, by I/O device decodes, acceptance and execution CCW order, is carried out CCWI/O operation.The one or more CCW that are configured to carry out in proper order form CCW channel program and as one or more I/O operations, carry out respectively.

Optical-fibre channel expansion (FCX) function is optional function, and it provides the information of the transmission mode channel program consisting of transmission control word (TCW), transmission control word (TCW) given transmission command control block (TCCB) and transmission state piece (TSB).TCCB comprises transmission command region (TCA), and this district inclusion one or more (for example, maximum 30) is taked the list of the I/O order of unit command word (DCW) form.TCW and TCCB thereof can specify read or write operation.In one embodiment, FCX bidirectional data transmission function can be arranged in the system of supporting transmission mode operation, the in the situation that of connection device 116 and control module 118 support bidirectional data transfers, this system allows host computer system 102 to transmit input and output data by single transmission mode I/O operation simultaneously.When control module 118 identification bidirectional data transfers, TCW and TCCB thereof can specify to read with data writing according to equipment simultaneously and transmit.

Under transmission mode, single transmission command word (TCW) specifies in the position (and the position in the storer 106 or 108 of one or more data areas) in the TCCB storer sending in single message (but not each independent CCW) in command mode.Control module 118 by decoding, accept and carry out TCCB and comprising each DCW carry out transmission mode I/O and operate.If ORB specifies TCW channel program, channel subsystem 114 is used the information in specified TCW that TCCB is transferred to control module 118.After TCCB is transferred to control module 118, the content of TCCB is ignored by channel subsystem 114, and these contents are only meaningful to the I/O equipment 116 of control module 118 and association thereof.

In the exemplary embodiment, control module 118 produces response message in response to execute channel program.In some instances, control module 118 is execute channel program and directly produce response message not, for example, and in order to notify channel subsystem 114 channel programs not carry out.Control module 118 can comprise that a plurality of elements are to support communicating by letter between I/O communication adapter and I/O equipment, and supports channel program execution.For example, except one or more queues, timer and register, control module 118 can also comprise that steering logic is to analyze and processing messages, thereby promotes communication and status surveillance.

Fig. 2 illustrates the embodiment of transmission control word (TCW) 140, and this transmission control word is for example stored in, in main system (, primary memory 106) and specifies at least one from passage 128, to be transferred to the controll block of control module 118.In one embodiment, controll block is transmission command controll block (TCCB), and its content will be transferred to control module 118 and I/O equipment 116 is processed.When TCW140 specifies TCCB, TCCB comprises the TCA that specifies one or more unit command words (DCW) and associated selection thereof.Except the control data of specify initiating to comprise in the DCW(TCCB of order of data transmission), TCW140 specifies one or more storage areas that wherein comprise data.

In one embodiment, TCA comprises transmission TCA expansion (TTE) order, and it is in order to transmit the DCW that can be included in TCCB and/or to control other DCW outside data and/or control data that this order is provided.TTE is transferred to control module (comprising at least one DCW) by TCA expansion (TCAX) and is regarded as the logical extension (for example,, by last DCW of TCCB being linked to a DCW of TTE) of the TCA associated with it.

Refer again to now Fig. 2, the embodiment of TCW140 is 64 byte controll blocks of appointment on 64 byte boundaries.TCW comprises a plurality of field described below.

For example, a plurality of attribute field 142 indications are being used directly or input data, output data or TCCB are searched in indirect data addressing.Output transmission indirect data addressing (TIDA) field indication output data are direct still indirectly addressed.For example, when word 0, the position 7 of TCW140 is 0 and specifies while exporting data, exports data address field 144 and specifies the outputs data bits in definitely storage to put.When position 7 is 1, the specific address that output data address field 144 is specified the TIDAW in TIDA word (TIDAW) or TIDAW list (TIDAL), one or more outputs memory location is specified respectively in this address.Input TIDA field indication input data are direct still indirectly addressed.For example, when word 0, position 5 is 0 and while specifying input data, and input data address field 146 is specified the specific address (that is, wherein the position of storage input data) of input memory locations.When position 5 is 1, the specific address that input data address field 146 is specified the TIDAW in TIDAW or TIDAL, one or more inputs memory location is specified in this address.Transmission command controll block TIDA(TCCB-TIDA) field indication TCCB is direct still indirectly addressed.For example, when word 0, position 6 is 0 o'clock, the TCCB specific address that TCCB address field 148 is specified TCW, and when position 6 is 1, the specific address that TCCB address field 148 is specified TIDAW or TIDAL, one or more TCCB position is specified in this address.

TCW140 also comprises transmission command controll block length (TCCBL) field 150, and this field is with the byte number designated length of TCCB.For example, TCCBL field comprises signless integer, its value (for example, when for one-way data transmission, be added to 20 or when be added to 24 for bidirectional data transfers) with the length of byte number appointment TCCB.

When indication will be transferred to the byte number in primary memory 106, read operation (R) field 152 non-zeros (for example, the position 14 of word 1 is 1).When indication will be transferred to the byte number in primary memory, write operation (W) field 154 non-zeros (for example, the position 15 of word 1 is 1).If R field 152 and W field 154 are at 1 o'clock, will recognize program checkout condition, unless target device 116 and control module 118 are supported bidirectional data transfers.If W position be 1 and TCW for inquiry is during TCW, recognizer is checked to condition.

The position of the output data that 144 indications of output data address field are any will send to equipment in storage.For example,, when the position of word 1 15(W field bit 154) be 1 and attribute field 142(output TIDA sign) position 7 while being 0, word 2-3 specifies 64 outgoing positions in definitely storage.When W position is 1 and output TIDA while being masked as 1, word 2-3 specifies TIDAW or the TIDAW list ，Gai position, 64 positions in absolute storage to specify one or more outputs memory location.146 indications of input data address field, when receiving any input data from equipment, are stored the position of these any input data.For example,, when the position of word 1 14(R field bit 152) be 1 and the position 5(input TIDA sign of attribute field 142) while being 0, word 4-5 specifies 64 input positions in definitely storage.When R position is 1 and input TIDA while being masked as 1, word 4-5 specifies TIDAW or the TIDAW list ，Gai position, position in absolute storage to specify input memory location.

The address of the transmission state piece of transmission state block address 156 appointment TCW in storage.For example, 64 positions of the transmission state piece of word 6-7 appointment TCW in definitely storing.

One or more TCCB(are direct or indirect for 148 appointment of transmission command controll block address field) address.For example, if TCCB-TIDA position (position 6 of attribute field) is 0, word 8-9 specifies 64 positions of TCCB in definitely storing.When TCCB-TIDA position is 0, TCCB is designated as in the continuum that resides in storage.If transmission command controll block TIDA position is 1, word 8-9 specifies TIDAW or 64 the position ，Gai position of TIDAW list in definitely storing to specify the position of TCCB in absolute storage.When TCCB-TIDA position is 1, TCCB can be designated as in the discontinuous region that resides in storage.

The output word joint number that output count area 158 is specified TCW.For example, when the 15(W position, position of word 1) while being 1, the signless integer tale of the output byte that word 10 comprises TCW.The input word joint number that input count area 160 is specified TCW.For example, when the 14(R position, position of word 1) while being 1, the signless integer tale of the input byte that word 11 comprises TCW.

If TCW specifies demand operating, inquire TCW address field 162 positions of indication inquiry TCW in storage.For example, when TCW is specified in START SUBCHANNEL instruction, do not check the word 15 of TCW.But, when CANCEL SUBCHANNEL instruction is specified unsettled as the startup of TCW channel program, but not during the unsettled subchannel of state, by the position 1-31 of the word 15 of START SUBCHANNEL appointment, specify the inquiry TCW of demand operating for initiating subchannel in the absolute position of storage.If when sending CANCEL SUBCHANNLE, word 15 comprises 0, does not initiate demand operating.When sending CANCEL SUBCHANNLE, the position 0 of word 15 is necessary for 0, otherwise recognizer checks condition, and indication inquiry status of fail.When a position 1-31 who sends CANCELSUBCHANNLE and word 15 is not while comprising 0, the position 1-31 of word 15 must be on 64 byte boundaries designated storage location, otherwise recognizer checks condition, and indication inquiry status of fail.Can reserved word 14 so that inquiry TCW address field is expanded to 64.

With reference now to Fig. 3 and 4,, transmission command controll block (TCCB) 170 comprises that one or more independent orders are as a part for TCW I/O operation, and by channel path, is sent to control module 118 and/or equipment 116 by passage 128.TCCB170 makes passage needn't send a plurality of message or message unit, also the responsibility of executable operations is passed to control module in addition and eliminates the needs that control module 118 sends the response of each order.On the contrary, control module 118 can be carried out all orders and will when complete operation, send response.

The variable-length of TCCB170, can comprise header and tail information, and one or more (for example, from 1 to 30) order is as unit command word (DCW), these unit command words carry out logical connection (for example, forming chain), to can be carried out in order by control module 118.TCCB170 can be used as single Coutinuous store piece and exists, and also can be used as a plurality of discontinuous storage blocks and exists.For example, the TCCB TIDA in above-mentioned TCW140 indicates whether be used to specify TCCB resides in Coutinuous store.

The example of TCCB is shown in Fig. 3 and 4.As shown in Figure 4, TCCB170 can send to control module 118 from passage 128, and it is as a part for transmission command message unit (IU) 172, and this message unit is sent to control module 118 to initiate I/O operation.In one embodiment, transmission command IU172 is comprised of 8 byte SB-4 174, heel 4 byte transmission command head (TCH) 176 and TCCB170.TCCB170 comprises 16 byte transmission command region heads (TCAH) 178, elongated transmission command region (TCA) 180 and transmission command region tail (TCAT) 182.TCAT182 may further include 4 byte LRC field 184,4 byte data transmission length (DL) fields 186, for bidirectional operation, comprises the two-way reading out data transmission of 4 byte length (BRDL) field 188.These fields will be further described below.

With reference now to Fig. 4,, SB-4 174 provides FC-4 addressing information to transmit data with recognition logic path and equipment 116.SB-4 174 provides channel image ID and the control module ID that comprises the logical path between passage 128 and control module 118, and the information of device id.

With reference now to Fig. 5,, TCH176 comprises the information of the equipment operating of relevant TCCB170 and association thereof.In one embodiment, TCH176 comprises 4 bytes, and immediately following the SB-4 in transmission command IU172 174.TCH176 comprises such as length field (" L1 ") 190, reads field (" R ") 192 and write the field field (" W ") 194.L1 field (be for example positioned at position 24-29 on) specifies the length (representing with number of words) of TCA180 to add the 1 word LRC field 184 immediately following TCA180.For example, for the control module 118 of not supporting bidirectional operation, the total amount of data of transmitting in transmission command IU172 equals L1 field and adds 8(, and L1 field adds 2 word SB-4 heads, 1 word TCH, 4 word TCAH and 1 word DL); Otherwise, the transmission command IU completeness error that control module identification is caused by data counts mistake.For the control module of supporting bidirectional operation, the total amount of data of transmitting in transmission command IU172 equals L1 field and adds 8(, L1 field adds 2 word SB-4 heads, 1 word TCH, 4 word TCAH and 1 word DL) or L1 field add 9(, L1 field adds 2 word SB-4 heads, 1 word TCH, 4 word TCAH and 1 word DL, and for 1 word BRDL of bidirectional operation); Otherwise, control module is caused identification transmission command IU completeness error by data counts mistake.If unidentified to transmission command IU completeness error, in TCCB, LRC inspection is searched and can carry out in the position of LRV based on L1 field.

Reading (R) field 192 specifies TCA180 to comprise one or more reading or input command.In the embodiment of Fig. 5, R field 192 is R position, position 30, and when being set as 1, the order that this indication TCA180 comprises one or more transmission reading out datas.When R position is set as 0, TCA180 does not comprise the order of any transmission reading out data.When R position be 1 and W position (for example, position 31) be 0 o'clock, this operation is called as read operation.When R position and W position are all set as 0, TCA180 does not comprise that any transmission is read or the order of data writing, thereby indication I/O operates not performing data transmission.When R position and W position are all set as 1, TCA180 can comprise transmission simultaneously and read the order with data writing, and this operation is called as bidirectional operation.But do not support bidirectional operation if specify bidirectional operation control module 118, or but control module 118 supports bidirectional operation transmission command IU172 to comprise BRDL field 188, equipment 116 or control module 118 identifications are by the TCH content false that reads-write conflict and cause.When R position is 0 and control module 118 or equipment 116 while running into the order of attempting transmission reading out data in TCA180, identification attempts by invalid reading the TCCB content false that causes.

Writing (W) field 194 specifies TCA180 to comprise one or more writing or output command.In the embodiment of Fig. 5, W field is W position, position 31, and when being set as 1, the order that this indication TCA180 comprises one or more transmission data writings.When this position is set as 0, TCA180 does not comprise the order of any transmission data writing.When W position is 1 and R position (position 30) while being 0, this operation is called as write operation.When W position be 0 and control module 118 or equipment 116 run into and in TCA180, specify while writing the order of order, the TCCB content false that identification is caused by invalid Writing condition.

With reference now to Fig. 6,, the embodiment of TCA head (TCAH) 178 comprises the information of relevant TCA180 and the operation of wherein describing, for example TCA length and equipment indication.In this embodiment, the byte 3 of word 1 is " L2 " length field 196, this field comprise specify TCA180 length (representing with byte number) without symbol bigit, add the word 2 and 3 of TCA head, add the 4 byte LRC fields 184 immediately following TCA180.Service operations code field 198(for example, the byte 0-1 of word 2) comprise the signless integer value of specifying by the action type of TCCB appointment.For example, the hexadecimal value of ' 1FFE ' indication SB-4 equipment I/O operation, the hexadecimal value indication SB-4 equipment support function of ' 1FFF '.Priority number field 200(for example, the byte 3 of word 2) comprise control module I/O priority number.

With reference now to Fig. 7,, transmission command region (TCA) the 180th, elongated region, this district inclusion one or more (for example, from 1 to 30) is ordered as unit command word (DCW) 202.In one embodiment, TCA180 is the integer with 4 byte words.The DCW202 that controls data for designated equipment, TCA180 also comprises the control data associated with each DCW202.Each DCW202 of specified control data reduces one or more DCW by maximum DCW capacity, specifically depends on the size of order association data.For appointment, input or output the DCW202 of data, TCW140 specifies the storage area of one or more associations, and DCW specifies the byte count that will transmit.In one embodiment, the largest amount of TCA is 240 bytes.As shown in the embodiment of Fig. 7, while there is sufficient space in the TCA180 of whole DCW202, DCW202 on closelying follow a DCW202 or with on start in the word boundary of the associated control data of a DCW202.Last DCW202 in TCA180 specifies while not being the control data of integral words, and follow-up LRC field 184 starts in the word boundary immediately following control data.

For some equipment, the list of DCW202 can expand to the capacity over TCA180.In this case, TCA expansion (TCAX) field can be designated as and comprise other DCW, and just as TCAX is output data, transmits (for example,, as exporting the part transmission of transmitting data I U).But TCAX is regarded as the logic continuity of TCA180, but not transmission data.TCAX specifies in TCA180 by transmitting TCA expansion (TTE) DCW.TCAX and TTE DCW are further described below, and the embodiment of TCAX is shown in Figure 12 and 13.

As shown in Figures 3 and 4, TCCB can comprise transmission command region tail (TCAT) 182, and it provides the additional information of relevant TCCB, comprising various count informations.In one embodiment, when specifying one-way data transmission (R position or W position are made as to 1) or while not specifying any data transmission (the R position in TCW and W position being made as to 0), the length of TCAT182 is 2 words simultaneously.When specifying bidirectional data transfers (the R position in TCW and W position being made as to 1), the length of TCAT182 is 3 words simultaneously.

For example, when specifying one-way data transmission, transmission counting or data length (DL) field 186 are specified 32 signless integer countings (" transmission count value ") of the total data that will transmit.When specifying read operation (TCW R position is 1), the value in the transmission count area in TCAT can be by specifying respectively the count word segment value summation in the DCW202 that reads type command to determine.This sum is rounded up as immediate 4 multiple, and the sum rounding is 4 times of growths to reach transmission count value.When specifying read operation, transmission count value should equal the value in TCW input count area 160, and this value rounds up as next multiple of 4, adds 4.

When specifying write operation (the W position in TCW is 1), to specifying the count word segment value summation in the DCW202 that writes order.In addition, below all transmission command DCW(of the transmission of given transmission order metamessage (TCMI), further describe) in count word segment value add that the size of the reserved field in TCMI is added to (the large I that it may be noted that TCMI reserved field is made as 0) on this sum.The controll block inspection (CBC) of any TIDAW appointment or Cyclical Redundancy Check (CRC) tale byte and byte of padding are added on this sum.This sum is rounded up as immediate 4 multiple, and the sum rounding is 4 times of growths to reach transmission count value.When specifying write operation, transmission count value should equal the value in TCW output count area 158, and this value rounds up as next multiple of 4, adds 4.When neither specifying read operation, also not specifying write operation (W position and R position in TCW are 0), transmission count value should be 0.

When specifying bidirectional data transfers, DL field 186 is for writing 32 signless integer countings counting and specify the total output data that will transmit.Transmission count value in DL field (writing count area) in TCAT182 is determined for write operation according to described above.Two-way reading out data length (BRDL) field 188 is specified 35 signless integers of the total input data that will transmit.The transmission count value of BRDL field 188 is determined for read operation according to described above.

In one embodiment, for write operation or bidirectional operation, DL field should comprise 4 bytes without symbol bigit, this integer specify will be by channel transfer to control module with the byte number of executable operations and comprise all centres and final byte of padding and CRC byte, if COB is included in the first transmission data I U of write operation, it also comprises COB, any COB byte of padding and COBCRC byte.If TTE DCW is arranged in TCA, DL field also comprises TCAX, any TCAX byte of padding and TCAX CRC byte.

Fig. 8 and 9 is respectively that general introduction determines that the TCW of unidirectional and transmitted in both directions inputs the table of counting, output counting and TCAT transmission count value.

For bidirectional operation, two-way reading out data length (BRDL) field comprises that 4 bytes are without symbol bigit, this integer is specified and is wanted controlled unit to be transferred to passage with the byte number of executable operations, and comprises that any byte of padding (if being not yet positioned in word boundary) that need to be rounded to word boundary adds 4 byte CRC.For non-bidirectional operation, if transmission command IU comprises BRDL field, equipment should be identified by reading and write the TCH content false that conflict causes.

With reference now to Figure 10,, unit command word (DCW) 202 is specified the order that will carry out.For the order of initiating specific I/O operation, its is specified the byte count that is performed operation, the operation that need to carry out when with being transmitted of storage, and other option.According to the operation of order appointment, by input data address field 146 or the output data address field 144 of TCW140, specify the one or more storage areas associated with DCW data transfer operation, TCW140 specifies the TCCB170 that comprises DCW202.Directly or indirectly whether input data address field 146 or output data address field 144 the input TIDA of designated store in TCW140 specify with output TIDA sign.

In one embodiment, DCW202 is 8 byte controll blocks, in the TCW140 of this piece in word boundary, specifies.DCW202 comprises the field such as command code field 204, control attribute field 206, control data counts 208 and DCW data counts 210.

Command code field 204(for example, the position 0-7 of word 0) specify the operation that will carry out.Whether order effectively device dependent and depend on the value of service operations code field 198 in TCAH178.Basic command comprises and reads, writes, controls, detects and transmit.Operation below channel subsystem 114 differentiations: control, forward output (writing), forward are inputted (reading, detect, detect ID), reverse input (reverse read), branch's (transmitting in passage) and transmitted.When carrying out, some order can not cause data transmission, but causes equipment chain together and when meeting all chaining command conditions, start to carry out next order.Each basic operation is described below.

Reading order initiates to carry out the equipment of realizing to the equipment operating of channel data transmission.Write order initiation execution and realize passage to the equipment operating of device data transmission.Control command initiates to carry out the equipment operating that the control data that provide in DCW are provided.These sense commands are similar to reading order, and just data are obtained from detecting indicator, but not obtain from the source of recording.Control command and associated control data thereof provide the management of specific I/O equipment and the control of equipment during carrying out I/O order.Transmission command, for managing I/O operation with by the data transmission of channel path, is not to set specific order.Controll block these order management such as Cyclical Redundancy Check (CRC) data checks the transmission of data, and the transmission of transmitting other DCW in data I U.

Control data (CD) count area 208 and specify the control data word joint number associated with DCW202.For example, the byte 3 specified control data lengths (representing with byte number) of word 0.If command code is specified the order need to control data, and the control data counts of byte 3 appointments of word 0 is less than the required counting of order, and identification equipment checks conditioned disjunction TCCB content false.If command code is specified the order need to control data, and the byte 3 of word 0 comprises 0 or comprise and specify the value that surpasses TCA end (or surpass the TCAX of appointment end), and identification equipment trace routine checks conditioned disjunction TCCB content.

DCW data count field 210 specific datas (for example, the data that transmit for read or write operation, that is, customer data) byte count, these data are specified for DCW202 by TCW.For example, DCW data counts is included in the word 1 of DCW202 of Figure 10, and specifies TCW for 32 signless integer byte counts in the storage area of this DCW appointment.210 indications of DCW data count field are during carrying out DCW, and the byte number that transmit between passage and control module, does not comprise any byte of padding or CRC byte.

With reference now to Figure 11,, in one embodiment, DCW202 comprises a plurality of control signs 206.Chain order (CC) indicates that 212 appointments need fill order link.After equipment end when current device operation normally completes and on identification equipment, chaining command causes carrying out next DCW202 in TCA180.In CC sign 212 last DCW in TCA, be set as 0.In the embodiment of Figure 10, the 9(CC position, position of word 0), when being 1, specified command link.When being 1, this is initiated while causing the current DCW of operating in of next DCW appointment normally to complete.When control data counts is 0, next DCW is immediately following the DCW in TCA or TCAX.When control data counts is not 0, next DCW is immediately following the control data that are rounded to word boundary for DCW appointment.In one embodiment, when chain order is masked as 1, the position of next DCW in TCA or TCAX by by 8 and CD count area in value be added on the position of current DCW, and upwards evidence obtaining is determined to nearest word boundary.If in the DCW of TAC, chain order is masked as 1, and next DCW position surpasses the end of TCA, and specifies TCAX, and next DCW is positioned at the beginning of the TCAX of appointment.

In one embodiment, control attribute field and comprise inhibition Length Indication (SLI) field 214.When passage 128 and control module 118 support DCW incorrect length function, (for example in SLI attribute field 214, provide a position, position 2), whether this control command link in incorrect length condition, occurs and when incorrect length condition controlled unit 118 detects, whether incorrect length is indicated in transmission response IU by this control module.If DCW data counts need to not mate for writing the data volume of DCW with equipment, if or DCW data counts do not mate with the data volume that can be used for reading DCW on equipment, incorrect length condition controlled unit detects.When passage and control module are not supported DCW incorrect length function, position 2 is retained and is made as 0 by passage, and controlled unit is ignored.

When SLI sign 214 is 1, incorrect length indication is suppressed.When CC and SLI sign is 1, chaining command occurs, and does not consider whether there is incorrect length condition.When SLI sign 214 is 1 and while there is incorrect length condition for current DCW, chaining command (if being instructed to) should be allowed to and control module continues to carry out next DCW.In one embodiment, SLI is masked as and should be set as 1, or otherwise activates in all DCW that need to suppress incorrect length indication.

If SLI is masked as 0 and have incorrect length condition for DCW, chaining command (if being instructed to) is not allowed to and control module 118 stops I/O operation.In channel subsystem 114, if SLI is masked as 0 and have an incorrect length condition, the processing of TCA180 stops and by the incorrect length of indicating in subchannel state, subchannel to be become to state unsettled.When incorrect length condition for DCW202, exist and DCW in SLI sign 214 while being set as 1, according to description performing data transmission below, otherwise terminating operation and should report the abnormal end condition of operation.

For reading DCW202, if DCW data counts is greater than the data volume that can be used for order on equipment 116, apply rule below.If CC sign 212 is 1(indication chain), the data available on equipment 116 is transferred to passage 128, and transmission byte of padding (being set as 0), to equal DCW data counts for the data volume of DCW202 transmission.The all data that are transmitted that comprise byte of padding are included in the required any CRC calculating of operation.If CC sign 212 is not indicated chain for 0(), the data available on equipment should be transferred to passage, should not transmit any excessive data or transmission byte of padding (being set as 0), to equal DCW data counts for the data volume of DCW transmission.The data that are transmitted add that any byte of padding should be included in the required any CRC calculating of operation.For this situation, whether transmit byte of padding model-free irrelevant.If DCW data counts is less than the data volume that can be used for order on equipment, only by the data volume that equals DCW data counts, for DCW202, be transferred to passage 128.The data that are only transmitted should be included in the required CRC calculating of operation.

For writing DCW202, if being greater than equipment 116, DCW data counts need to, for the data volume of ordering, apply rule below.If CC sign 212 is 1(indication chain), the data volume of DCW data counts appointment should be transferred to passage 128.The data that are transmitted should be calculated for operating required any CRC, and abandon the unwanted data of equipment 116.If CC sign 212 is not indicated chain for 0(), the required data volume of equipment 116 is transferred to control module 118.Excessive data is transferred to CRC word in the middle of next, or until the data counts of DCW run out.The all data that are transmitted are calculated for operating required any CRC.Need to be for the data volume of ordering if DCW data counts is less than equipment 116, the data volume of DCW data counts appointment is transferred to control module 118.The data that are transmitted are calculated for operating required any CRC.

For DCW data counts wherein, be greater than equipment 116 and need to for 0(, do not indicate chain for data volume and the CC sign 212 of ordering) write DCW202, the data volume that transmission equipment 116 is required.Then data continue to be transmitted, and insert next CBC, or until the total amount that will transmit equal DCW data counts until specify.Exemplary command code is shown in Figure 12, and this illustrates 6 TCW orders pointer to which sign of each command definition.Transmission command DCW is that a class is not specified particular data transmission order (that is, requested by the customer data of principal computer command), but appointment is carried out and the DCW of the transmission command of the support function of transmission mode I/O operative association.Transmission command DCW can specified control data, transmission that also can given transmission order metamessage (TCMI).TCMI comprises for controlling the data of the transfer function of I/O operation, for example, I/O mode of operation on equipment, relevant can not put into the information that maybe can be included in other DCW of current TCCB, and controll block inspection (CBC) information such as Cyclical Redundancy Check (CRC) data.

When transmission command DCW appointment is transferred to equipment by TCMI, TCMI is transmitted (for example,, in transmission data I U) as output data.The size of TCMI is relevant to order, for example, be 4 multiple.When even-multiple that the size of TCMI is 4, TCMI can expand by 4 reserve bytes, use TIDAW to specify territory, output block, insert CBC sign is 1 in last TIDAW that is used to specify the storage that comprises TCMI, chain command bit is 1 in the transmission command DCW that specifies TCMI, and follow-up DCW specifies the transmission of TCMI or output data.It may be noted that, when transmission command, specify TCMI is transferred to equipment, and owing to meeting above-mentioned all conditions and pass through 4 reserve bytes expansion TCMI, these 4 reserve bytes are not included in the data counts value in transmission command DCW, but be included in following value: the transmission count value being used to specify in count value in last TIDAW of the storage that comprises TCMI, the output count value in TCW and associated TCCB (is transmitted for one-way data, for transmitted in both directions, be included in writing in count value in associated TCCB).

In one embodiment, TCMI comprises inquiry message (by inquiry DCW), CBC offset blocks (by transmission CBC offset blocks DCW) and TCA expansion (by transmission TCA expansion DCW).

There is shown the embodiment of the data of a class transmission command DCW appointment that is called as transmission TCA expansion (TTE) order, this order is included in the TCA180 of TCCB170 and specifies TCA expansion (TCAX) 220 that will be transferred to control module 118.TCAX is regarded as the logical extension of TCA180.For some equipment 116, surpass the quantity that can be contained in the DCW in TCA180 with the list of the DCW202 of I/O operative association.In this case, can comprise in the end of TCW140 TTE DCW, this TCW as the TCAX220(of output data transmission for example specifies, in data transmission IU).The content of TTE DCW can comprise command code, and this command code comprises transmission TCA explosion command (for example, value 50hex).

For example, the variable-length of TCA180, largest amount is that 240, DCW has 8 bytes.Like this, in this example, can in TCCB, transmit maximum 30 DCW.But, for the DCW202 that specifies the control command that need to control data, control data immediately following each DCW202 in TCCB.Like this, the TCCB170 that comprises this type of order is restricted to and is less than 30 DCW.TTE DCW can be used for required other DCW that can not put into TCA180 of assigned I/O operation.

As shown in figure 13, TCA expansion (TCAX) is elongated region, and it is the logic continuity of TCA180 in another transmission command IU or TCCB, and comprises DCW list and associated control data thereof.TCAX comprises one or more other DCW for TCW I/O and associated control data (except transmitting at initial TCCB) thereof, can be sent and be operated required DCW list with expansion I/O by another TCCB or transmission data I U.In one embodiment, the integral multiple that the length of TCAX is 4.

As shown in figure 13, in one embodiment, TCAX220 comprises the control data of DCW202 and/or a upper DCW.When last information in TCAX220 is DCW202, the end of the meaningful information in the end definition of T CAX220 of this DCW202.Last information in TCAX220 is for controlling data, and these controls data are when finish on 4 byte boundaries, the end of the meaningful information in the end definition of T CAX220 of these control data.When last information in TCAX220 does not finish for controlling data and this controls data on 4 byte boundaries, byte of padding is appended in control data to reach the end of the meaningful information in the end definition of T CAX220 of 4 byte boundaries and padding data.When the size of the meaningful information in TCAX220 equals odd number divided by 4, there is no reserve bytes; Otherwise, immediately following 4 bytes of the meaningful information in TCAX220, be retained and should comprise 0.When the control data of last DCW202 in TCAX180 are included in TCAX220, controlling data is first data in TCAX220.The data based mode for TCA180 definition of other DCW in TCAX220 and control is processed.

In one embodiment, below TCOB DCW(, further describing) while not being arranged in TCA180, TTE DCW is the DCW202 in TCA180.When TCOB DCW is arranged in TCA180, TTE DCW is the 2nd DCW202 in TCA180.TTE DCW data counts is specified the length of TCAX220 and can is the integral multiple of 4 bytes.TTE DCW control data counts be 0 and TTE DCW in chain order sign be set as 1.TTE DCW data do not comprise TCAX CRC or TCAX byte of padding.

TTE order (TTE DCW) should be sent to the equipment that TTE order is supported in indication, and (for example there is particular maximum value in TCA length, 60 words) the control data of last DCW and in TCA extend beyond last byte in TCA, or TCA length is for example greater than 58 words and be sent out while needing one or more other DCW to operate for I/O.When COB is writing while providing in transmission data I U, TCAX should closely follow COB CRC.When not providing COB, what TCAX should operate by I/O first writes transmission data I U and sends.

Another kind of DCW is transmission CBC offset blocks (TCOB) DCW, and it is CBC offset blocks (COB) to be transferred to the order of control module.CBC data indication controll block checks data, for verifying the correct amount that inputs or outputs data in I/O operation transmission.In one embodiment, CBC data are Cyclical Redundancy Check (CRC) data, and COB is CRC offset blocks, and TCOB DCW is transmission CRC offset blocks DCW.Generally speaking, Cyclical Redundancy Check (CRC) is for being configured to detect the error detection code of the accidental change of the raw data of transmission between passage 128 and control module 118.The equipment (for example, passage 128) of enabling CRC calculates the binary sequence of brief, the regular length of each data block that will send or store, and this sequence is appended in data, thereby forms coded word or " CRC word ".For example, when providing CRC to produce, passage 128 produces CRC and is inserted in the value of the end calculating of last data byte in transmission data.When CRC word is received or read, receiving equipment (for example, control module 118) its check the value and the value by the new calculating of data block are compared, or ground of equal value, in whole coded word, carry out CRC and the check the value drawing and expection surplus constant are compared.If check the value does not mate, in piece, comprise the mistake in transmission data.Although be described as CRC data in CBC embodiment herein, be not limited to this.

Example T COB DCW specifies COB is transferred to equipment.This example T COB has the command code that comprises transmission CRC offset blocks order (for example, value 60hex).Chain order is masked as 1.When the CD of TCOB DCW counting 208 is not 0, COB specifies the CRC offset numbers in COB to be multiplied by 4 immediately following the TCOB DCW in TCA180 and CD counting 208.When CD counting 208 is 0, COB is designated as the TCMI in TCW, and the position of COB is specified by the output data address field 146 in TCW, and this count area specifies the CRC offset numbers in COB to be multiplied by 4.

As shown in figure 14, COB222 specify to write or the transmission data of reading out data transmission (for example,, by transmission data I U) in the position of middle CRC word.In one embodiment, and when the DCW202 in TCA180 comprises TCOB order (, TCOB DCW), COB is provided.Middle CRC skew is between the data in data transmission IU and is positioned at the CRC word before IU end.COB222 comprises 1 word value list, is called as CRC skew 224, the byte offset of each middle CRC word in each skew identification transmission data.For example, COB is elongated controll block, and comprising 4 byte entries lists, the CRC that will be inserted into output data of each entry identification TIDAW appointment is offset.

In the embodiment shown in fig. 14, COB222 comprises 1 to the N+1 word (CRC offset word 224) of middle CRC skew.If COB222 provides in transmission data I U, COB can also comprise 0 or 1 word of byte of padding and 1 word of CRC.Byte of padding can be provided, and is not in the word boundary of double word boundary so that the word that comprises CRC is positioned at.The last character of COB should comprise CRC, and this CRC contains middle CRC skew 0 to N and body is filled word (if existence).If the control data of COB as TCOB DCW are provided, should have COB to fill or CRC, and control data counts and should equal 4 times of middle CRC offset word hop count in COB.

For write operation, TCOB DCW specifies COB to be transferred to equipment 116.TCOB DCW command code comprises it being for example the TCOB order of value 60hex.The position of COB is by controlling that data counts is determined and can writing in transmission data I U and provide in first of I/O operation, or provides as the control data of the TCOB DCW immediately following I/O operation.Li8ru, when the CD of TCOB DCW counting is not 0, COB222 is immediately following the TCOB DCW in TCA180, and CD counting specifies the CRC offset numbers in COB to be multiplied by 4.When CD is counted as 0, COB222 is designated as the TCMI with output data transmission, and the output data address field 144 of the position of COB in TCW140 specified.

The CRC skew 224 indications skew (with byte number represent) relative with the first byte of data in transmission data I U in the middle of each in COB222.If COB222 provides in transmission data I U, by the first byte that is written into the data of transmission, be to closely follow the first byte (if TCAX220 is not provided) of COB CRC although or the first byte (if TCAX is provided) of TCAX CRC.If provide COB to control data as DCW in TCA180, it by the first byte that is written into the data of transmission, is the first byte (if TCAX220 is provided) in transmission data I U.When being provided in transmission data I U, COB writes in transmission data I U and provides in first of I/O operation.

Another type transfers order DCW is inquiry DCW, and it is for determining the state of the TCWI/O operation on equipment 116.Inquiry command is not initiated operation on equipment 116, can not affect the state of equipment 116, and the loyal and steadfast and associated logical path associated with equipment 116 of can not resetting.Exemplary interrogation DCW comprises inquiry command code (for example, comprising value 40hex).Except command code, SLI sign, counting and CD count area, all other fields in DCW all should comprise 0, otherwise comprise the program checkout condition that equipment Inspection is arrived.If the CD counting of inquiry DCW is greater than 0, specify inquiry data.

To logical path and the equipment 116 of carrying out TCW I/O operation carry out demand operatings, to obtain the data relevant to mode of operation on equipment 116.In one embodiment, the TCCB170 of demand operating comprises the have inquiry command code single DCW of (for example, X ' 40).The TCAH178 of demand operating can comprise and is set as 1 to specify the R position of reading out data transmission for operation.When control module 118 is accepted to specify the transmission command IU of inquiry command, on control module 118, identify demand operating.When identifying demand operating and control module 118 on control module 118 and can successfully carry out inquiry command, control module 118 can provide state in transmission response IU, comprising the inquiry extended mode of describing the logical path of inquiry transmission command IU appointment and the state of device address.

With reference now to Figure 15,, shown in it, carry out the embodiment of the method for transmission mode I/O operation 300.Described method comprises one or more stage 301-305.In one embodiment, described method comprises with described order and carries out all stage 301-305.But some stage can omit, some stage can add, or can change the order in stage.

In the stage 301, the principal computer (instruction (for example, START SUBCHANNEL) that for example, OS110) execution makes ORB be transferred to channel subsystem 114 and specifies TCW140.By channel subsystem 114, checked to determine whether TCCB170 to be transferred to I/O equipment 116 in one embodiment, to specific to the trap state program checkout condition relevant with the availability of the TCW field of transmission appointment TCCB170.If this type of program checkout condition exists, do not transmit TCCB170 and recognizer and check condition.For example, check the TCCB address field 148 of specifying available storage location.If TCCB-TIDA is masked as 1, also check that 148 appointments of TCCB address field are positioned at the borderline address of quad word.Further describe other program checkout condition below.

In the stage 302, when passage 128 by the controll block that comprises TCW140 (for example, transmission command controll block (TCCB) 170) and when the transmission command IU172 of associated control information sends to selected equipment 116, use I/O equipment to initiate TCW I/O operation (for example,, by control module 118).In one embodiment, for example, as message unit (IU), carry out between passage 128 and control module 118 with the execution of I/O operation and the information of equipment operating (, order, input data and output data) association.In one embodiment, IU takes the form of SB-4 message unit (IU).

In one embodiment, IU or other message, by one or more exchanges, send between passage and control module.All SB-4 device level functions that link is controlled functions and carried out under command mode for all SB-4, the exchange that need to be formed by two one-way exchange to (exchange by passage 128 for sending IU, another exchange by control module 118 for sending IU).For the device level function of carrying out, use single two-way exchange, also referred to as transmission exchange under transmission mode.The IU being sent by passage 128 between the SB-4 device level functional period of carrying out under SB-4 link control function or fill order pattern is limited to an exchange, and the IU being received by passage is during operation limited to another exchange.The exchange that passage 128 sends IU is called as departures exchange, and the exchange that passage 128 receives IU is called as inbound exchange.When departures exchanges and inbound exchange are present between passage 128 and control module 118 to carry out identically while linking level or device level function simultaneously, we think to exist and exchange rightly, and control module 118 is regarded as being connected to passage 128.The channel program using in single connection is only used an exchange right.If deleted connection because closing exchange during execute channel program, produce new exchange to complete channel program.Passage 128 can be by sending as the IU(of uncalled order or uncalled control information kind or initiating IU) (opening new exchange) initiates to exchange right.Control module 118 can by send as uncalled control or uncalled data message kind, initiate to exchange right.

The UI that passage and control module send carry out I/O operation (carrying out) under transmission mode during is limited to single two-way exchange (being called transmission exchange).Passage 128 is initiated IU by the transmission command IU(sending as uncalled order kind) open and transmit exchange.Passage 128 can be opened a plurality of transmission exchanges, and each exchanges for different equipment 116 or for the same equipment 116 being positioned on Different Logic path.Can open new transmission exchange for the particular device on logical path, prerequisite is for this equipment and logical path, to exist for carrying out the transmission exchange of demand operating; Otherwise passage 128 waits for that existing transmission exchange or exchange are to closing, and then could initiate new transmission exchange for the equipment on logical path.

In the stage 303, control module 118 receives TCCB170 and transmission command IU172, and can accept TCCB170 meeting under specified conditions.When receiving transmission command IU172, TCCB170 is regarded as being positioned on control module 118, until the TCCB170 on control module 118 carries out, is considered to complete.If because error condition is not accepted transmission command IU172, transmission response IU is turned back to passage 128, and original state sign is made as to 1 to indicate initiation on equipment 116 to make a mistake before carrying out TCCB170.Control module 118 can the following describes at transmission-response IU() in state and I/O expansion conditions field in provide error message with identification transmission command IU mistake.In one embodiment, the exemplary condition the following describes should be satisfied, to accept transmission command IU172 on control module 118:

1) transmission command IU meets following integrity checking:

A) for the control module of not supporting bidirectional operation, LI field in TCH adds 8 should specify a data volume, make this data volume equal the data volume that control module receives for transmission command IU, otherwise, the transmission command IU completeness error being caused by data counts mistake should be identified;

B) for the control module of supporting bidirectional operation, LI field in TCH adds 8 or 9 should specify a data volume, make this data volume equal the data volume that control module receives for transmission command IU, otherwise, the transmission command IU completeness error being caused by data counts mistake should be identified; And

C) the LRC field in TCCB should be effective, otherwise, should identify the transmission command IU completeness error being caused by invalid LRC.

2) logical path of appointment should be set up, otherwise " not setting up logical path " mistake will be identified;

3) for those, need equipment to be mounted and ready order, device address should be specified and has been mounted and ready equipment, otherwise will identify " address is abnormal " condition;

4) if control module does not support bidirectional data transfers or transmission command IU not to comprise BRDL field, should not be in TCH R position and W position are made as to 1, otherwise will identify TCH content false;

5) TCCB in transmission command IU should meet all conditions below, otherwise will identify TCCB content false:

A) should to specify be just in time the length of 8 bytes to L2 field, and this length is greater than L1 field, and comprise and be at least the value of 20 bytes and be not more than 252 bytes;

B) byte 1 of the word 0 of TCAH should be 0;

C) the form control field in TCAH should equal hex ' 7F ';

D) the service operations code in TCAH should comprise effective value (referring to 8.13.4.4);

E), if R position and W position are all set as 0, data length (DL) field should be by 0;

6) if operating, carries out for logical path and the device address of appointment in transmission command IU another TCW I/O, service operations code should specify the command code in a DCW of hex ' 1FFF ' and TCA should specify inquiry command code, otherwise will identify " without inquiry the second operation " mistake.

In one embodiment, when transmission command IU172 is sent out, passage 128 is considered to have connection, and when transmission command IU172 is accepted, control module 118 considers that existence connects.Like this, passage 128 is indifferent to the progress whether control module 118 has been accepted TCCB170 or be indifferent to I/O operation on equipment 116, until control module 118 is used transmission response IU to stop I/O operation.In one embodiment, passage 128 can setting-up time window, for this time window, from control module, receives response, if so that passage is not accepted transmission response IU in this window, just that passage can be identified transmission command is overtime.

In the stage 304, when TCCB170 is accepted, control module 118 is processed TCA180 and carries out each DCW202.Performed DCW202 is identified as current DCW.When DCW202 be transmission mode program the one DCW(, the DCW in TCCB) and carried out by I/O equipment 116 is selected, or when during chaining command, when follow-up DCW202 takes over the control of I/O operation, this DCW202 becomes current DCW.A DCW who carries out can be regarded as being arranged in the skew 0 of TCA180 of TCCB170.Other DCW of each in channel program is arranged in TCA180 (or TCAX220), and uses when I/O equipment 116 needs DCW.

DCW chain order (CC) sign of chaining command in DCW controlled.This sign specifies in the operation of taking while being finished current DCW.Be linked between the continuous DCW in TCA and occur.When specifying TCAX, link also occurs between the DCW in the DCW of last in TCA and TCAX, and occurs between the continuous DCW in TCAX.When the link of current DCW specified command, and while exception condition not detected during operation, completing of current DCW causes next DCW become current DCW and carried out by equipment.If specify the skew of TCAX and next DCW to surpass the end of TCA, chain continues a DCW of TCAX, and the skew that its TCAX skew is calculated by use deducts TCA length and determines.Like this, chaining command is carried out with the descending of TCA skew, and then, when specifying TCAX, TCAX is offset.If there is the condition (unless the SLI field 214 in DCW is activated) or incorrect length abnormal such as concern, equipment inspection, unit; inference operations sequentially; and the state associated with current operation causes producing interrupt condition, in this case, do not carry out new DCW.

During DCW101 in processing TCCB170, by one or more transmission data I U, between passage 128 and control module 118, send the requested data that operate transmission by I/O.Read operation is only carried out reading out data transmission, and data writing transmission is only carried out in write operation, and bidirectional operation can be carried out to read with data writing simultaneously and transmits.

With reference now to Figure 16,, for write operation or bidirectional operation, passage 128 sends to control module 118 to transmit the data writing 312 for operating by one or more transmission data I U310.For read operation or bidirectional operation, control module 118 sends to passage 128 to transmit the reading out data 316 for operation appointment by least one transmission data I U314.Byte of padding 318 can be included in the last character in the data area for its calculating CRC, and when the data area that will contain is not integer number of data word, is used to data area to be filled into next word boundary.This is applicable to the data area that will be contained by COB, centre and final CRC.Value for byte of padding is relevant with model.

When transmission data I U is passage 128 or control module 118 last transmission data I U that operation sends for TCW I/O, final crc field 320 is included in transmission data I U310,314.In one embodiment, final crc field 320 comprises 32 redundancy check codes of word alignment.For read or write operation, the DL field in TCCB is specified the data volume of transmitting during operation, and this data volume can comprise be necessary filling and CRC byte.For bidirectional operation, the DL field of TCCB170 is specified the data volume of the data writing hop transmission for operation, and BRDL field is specified the data volume of the reading out data hop transmission for operation.These data volumes can comprise be necessary filling and CRC byte.

Between data writing transmission period, data are transferred to control module 118 by one or more transmission data I U310 in the transmission exchange with TCW I/O operative association.In one embodiment, except first of operation writes transmission data I U310, passage 128 also requires to obtain the ready IU of transmission from control module 118, then could send each transmission data I U310.Control module 118 can transmit ready IU request excessive data by sending other, until it is for all data of DL field 186 appointments of the complete TCCB170 of write operation request.For write operation, next IU sending after the data transmission of the DL field appointment of control module 118 in completing TCCB is transmission response IU.For bidirectional operation, next IU sending after the data transmission of the DL field appointment of control module 118 in completing TCCB can be transmission data I U or transmission response IU.

Between reading out data transmission period, data are transferred to passage 128 by one or more transmission data I U314 in the transmission exchange with TCW I/O operative association.The data volume sending by each transmission data I U is determined by control module 118, and can be set as any value, as long as be no more than the value in DL field 186 for operating in the total amount of data of transmitting in all transmission data I U314, or for bidirectional operation, be no more than the value in BRDL field 188.For read operation, if the data volume that control module sends is less than the DL field in TCCB, the residual count in transmission response IU should be the poor of the data volume that sends of CU and the DL field in TCCB.If byte number poor of DL and the actual reception of passage, channel recognition device-level protocol mistake are not mated in the residual count that control module provides in transmission response IU.For bidirectional operation, if the data volume that control module sends is less than the BRDL field in TCCB, the BRDL residual count in transmission response IU should be the poor of the data volume that sends of CU and the BRDL field in TCCB.If byte number poor of BRDL and the actual reception of passage, channel recognition device-level protocol mistake are not mated in the residual count that control module provides in transmission response IU.

As shown in figure 16, one or more middle CRC words 320 can be arranged in the transmission data I U310 that passage 128 sends.Middle CRC word 320 provided the crc check to data area before the whole data area of transmission TCA180 appointment.When COB222 transmits in transmission data I U, COB CRC word 322 can be arranged in transmission data I U310.

Refer again to now Figure 15, in the stage 305, TCW I/O operation is stopped by passage 128 or control module 118.As exception condition or stop the result of the program initiated, passage 128 can initiate to stop TCW I/O operation.The result of carrying out as complete operation or conduct detect the result of exception condition during fill order, and control module 118 can be initiated terminating operation.Control module 118 can pass through to send transmission response IU, or under specific error conditions, exchanges to initiate to stop TCWI/O operate by termination.In one embodiment, control module 118 can initiate stop TCW I/O operation below in any case: executed TCA180(and TCAX, if designated) in all DCW202; When supporting that DCW incorrect length function and SLI214 are set as 0, the incorrect length condition of DCW detected; Equipment inspection condition detected; Exception condition such as error of transmission; Or identified another mistake that need to stop exchange.

With reference now to Figure 17,, in one embodiment, when the I/O operation of initiating by execution START SUBCHANNEL or the termination of the I/O sequence of operation, channel subsystem and equipment produce status condition.The concern of program can be interrupted or be caused by carrying out TEST PENDING INTERRPUTION instruction by I/O to these creations of condition.The counting of status condition and address and indication sequence of operation scope offers program with the form of subchannel status word (SCSW) 400.SCSW400 is stored in interrupt response piece (IRB) 402 between execution TEST SUBCHANNEL order period.When storage transmission mode IRB, the out of Memory of describing mode of operation is also stored in transmission state piece.

Generally speaking, carry out I/O operation, until equipment is notified main interruption status always.Main interruption status can be to initiate I/O operating period notified, or notified after a while.I/O can be carried out by channel subsystem and remove or hold function stops when equipment failure, program checkout, chain inspection, protection check or incorrect length condition being detected, or carries out and remove, stop or channel path function of reset stops as the result of carrying out respectively CLEAR SUBCHANNEL, HALTSUBCHANNEL or RESET CHANNEL PATH instruction.I/O interrupts providing for CPU the mode of changing its state on I/O equipment or subchannel in response to the condition occurring.These conditions can be caused by the external event on program, channel subsystem or equipment.

Cause the condition of initiating I/O interrupt request to be called as I/O interrupt condition.When interrupt condition is identified by channel subsystem, on suitable subchannel, indicate this interrupt condition.Then subchannel is considered as to state unsettled.Becoming the unsettled subchannel of state causes channel subsystem to produce I/O interrupt request.It is unsettled that I/O interrupt request keeps, until its CPU in being configured accepts, by channel subsystem, recalled, or be eliminated by carrying out TEST PENDING INTERRUPTION, TEST SUBCHANNEL or CLEAR SUBCHANNEL instruction, or reset and be eliminated by subsystem.When CPU accepts interrupt request and store associated interruption code, remove interrupt request.When unsettled interruption is eliminated by carrying out TEST PENDING INTERRUPTION, subchannel hold mode is unsettled, until remove associated interrupt condition during when carrying out TEST SUBCHANNEL or CLEAR SUBCHANNEL or at replacement subchannel.

I/O interrupt condition is generally removed by carrying out TEST SUBCHANNEL instruction, if carry out TEST SUBCHANNEL, thereby it is unsettled to specify subchannel to have I/O interrupt request, removes interrupt request and interrupt condition on subchannel simultaneously.Interrupt request and interrupt condition also can be removed by CLEARSUBCHANNEL.If the current startup of subchannel is unsettled, and if state comprises separately equipment end or comprises the equipment end of subsidiary control module end, the equipment end status condition that is produced by I/O equipment and provide after last I/O EO of start-up performance is reset on subchannel by channel subsystem, without producing I/O interrupt condition or I/O interrupt request.If other any mode bit is followed equipment end mode bit, channel subsystem produces I/O interrupt request indication lag condition code 1.When I/O operation stops because channel subsystem exception condition detected during sequence is initiated in order, the state of the interrupt condition of description is placed on subchannel, thereby it is unsettled to cause it to become state.If equipment Inspection is to exception condition, the device status field of associated SCSW is identified this condition.When chaining command occurs, by equipment, produce state and can not cause interrupting, and this state is not useable for program.

When channel subsystem detects following any interrupt condition, its initiates I/O interrupt request, needn't with devices communicating, or needn't be from equipment accepting state byte:

1) with by the last time, carry out the design mistake of relevance that START SUBCHANNEL is delivered to the ORB of subchannel;

2) in the one CCW of extraction for START SUBCHANNEL or the execution of RESUME SUBCHANNEL initiation CCW channel program, pause flag is made as to 1, and the not time-out of appointment inhibition interruption in command mode ORB; Or

3) design mistake associated with a CCW, TCW, TIDAW, TCCB extraction, data extraction, IDAW or MIDAW.

These interrupt conditions from subchannel (except the condition of suspending) can be attached other subchannel state indication, but equipment state indication is all stored as 0.

When the state that comprises equipment inspection is provided for the subchannel of forbidding or when equipment is not associated with any subchannel, channel subsystem sends to equipment by clear signal.But if the state providing does not comprise equipment inspection, state is accepted by channel subsystem and is dropped unsettled in the situation that not causing subchannel to become state.

Subchannel status word (SCSW) 400 offers program by the indication of descriptor channel status and associate device thereof.When transmission mode IRB402 is stored, other information of describing mode of operation and associate device thereof is also stored in the transmission state piece with operative association.If carried out stop, recovery or start-up performance, SCSW can describe the condition of terminating operation.

In one embodiment, SCSW storage when the subchannel of carrying out TEST SUBCHANNE and appointment is exercisable.SCSW is placed in to the word 0-3 of the IRB that is designated as TEST SUBCHANNEL operand.When carrying out SOTRE SUBCHANNEL, SCSW is stored in the word 7-9 of sub-channel information piece.

SCSW comprises a plurality of fields, for example deferred condition code (CC).If deferred condition code is not 0, is used to indicate whether to run at subchannel and starts unsettled or stop the condition of subchannel in subchannelland-device active state while suspending.In one embodiment, when setting deferred condition code 1, secondary status position is 1, and major state position is 0, current state can be relevant to command mode channel program, this program is specified (or implying by RESUME SUBCHANNEL instruction) by START SUBCHANNEL instruction, before this START SUBCHANNEL instruction is positioned at the START SUBCHANNEL of nearest execution, and the STARTSUBCHANNEL given transmission pattern channel program that this is carried out recently.For this situation, status modifier can be 1 in device status field.

Subchannel mode field is included in SCSW400 and by channel subsystem and is used to indicate aubchannel status condition.For example, subchannel mode field be included in SCSW word 2 position position 8-15 in.Subchannel status condition is detected by channel subsystem and indicates in SCSW.Except the condition that equipment failure causes, they can only relate to carrying out at channel subsystem and stop or occurring during start-up performance.Subchannel mode field is that state is unsettled and with just meaningful during any combination of major state, secondary status, intermediateness or alert status at each subchannel.When subchannel is the unsettled and indication lag condition code 3 of state, the content of subchannel mode field is meaningless.

Exemplary subchannel status condition is incorrect length condition, its byte number comprising in the storage area distributing for I/O operation be not equal to I/O device request or provide byte number time occur.When incorrect length condition is not installed and detected to FCX incorrect length deixis, by program checkout state, stop the processing of transmission mode channel program.When FCX incorrect length deixis has been installed, equipment is supported incorrect length indication, does not suppress correct length indication, and incorrect length condition detected, according to one of following reason, indicates incorrect length:

1) the long piece of input: reading or detecting operating period, equipment is attempted, after filling the primary memory area of having distributed, one or more bytes to be transferred to primary storage, if or equipment indicate and count greatlyr, can transmit more data.Extra byte number is not yet placed in primary storage.Counting in TSB (TSH) is 0.

2) the long piece of output: during write operation, equipment being finished the primary memory area of having distributed after from the one or more bytes of channel subsystem request, if or equipment indicate to count greatlyr, can transmit more data.In TSH, be counted as 0.

3) input short block: be not enough to fill the primary memory area that is assigned to operation at the byte number that reads or detect operating period transmission.Counting in TSH is not 0.

4) output short block: all information that equipment comprises in the primary memory area of having distributed stop writing before being transferred to equipment.Counting in TSH is not 0.

When current DCW has the SLI sign that is set as 1, suppress incorrect length indication.When TSH is meaningless, incorrect length indication is also meaningless.The existence of incorrect length condition suppresses chaining command, unless the SLI in DCW is masked as 1.

Subchannel extended mode field is included in SCSW400 and (for example, is arranged in the position position 24-31 of the word 2 of SCSW).When indicating in subchannel state, this field can comprise for further illustrating the information of following any condition reason: interface is controlled inspection, channel control check, channel data check, program checkout and protection check.If these position none in subchannel state byte in active state, the field of subchannel extended mode does not comprise any significant information.When indication is more than one during condition, interface is controlled inspection and is had precedence over other condition.

Subchannel expansion conditions field can also comprise inquires unsuccessfully (F) (for example,, in place 24) operative position.When being set as 1, the indication of F position, because program checkout, channel control check or interface are controlled inspection, causes demand operating failure.

Subchannel extended mode field can also comprise subchannel extended mode qualifier (SESQ) (for example, position 25-31).Group channel status field instruction program checks, interface is controlled inspection, when the failure of channel subsystem retry, protection check, data check or channel control check, this field can comprise out of Memory.The meaning of exemplary SESQ value and association thereof is shown in Figure 18 A-18B.

Figure 19-20 illustrate can controlled unit the 118 exemplary transmission response IU330 that send.Transmission response IU330 provides the TCW I/O state of operation, and this state can comprise normal termination state, or when exception condition being detected, comprises that indication operation exception stops the final state of reason.Transmission response IU330 can also comprise extended mode field, and this field provides further mode of operation.Transmission response IU can closing transmission exchange, also not closing transmission exchange.In one embodiment, whether exchange is transmitted response IU and is closed in FC-FS-3 head and indicates.If transmission exchange is not yet transmitted response IU and closes, passage can send the acknowledge IU that closes exchange after receiving transmission response IU.

In one embodiment, transmission response IU330 comprises SB-4 332, heel mode field 334, state LRC344 and optional extended mode field 346, and this extended mode field comprises for example from 32 to 46 bytes.When extended mode is provided, the last character that 4 byte expansion state LRC fields 340 can be used as transmission response IU330 provides.If extended mode byte number not in word boundary, adds byte of padding to extended mode to be rounded to next word boundary.SB-4 332 has the form that is similar to transmission command IU, and is set as for this exchange the SB-4 head equaling in transmission command IU.

With reference now to Figure 20,, the embodiment of state region 334 is for example 20 bytes and comprises the information that relevant TCWI/O operates." Status Flag 1 " field 336 comprises one or more exception codes, and these exception code controlled units 118 set to be reported in the exception condition that TCW I/O operating period detects.Exemplary codes comprises:

The device level that 0-is caused by address exception condition is abnormal;

2-is refused by the logical path link level that set up the condition does not cause;

3-resetting event notice-resetting event occurs on logical path and the equipment associated with transmission command IU.When this code is set in transmission response IU, the state confirmation of control module solicited status.If receive state confirmation, on equipment for logical path replacement resetting event condition; Otherwise it is unsettled that resetting event condition keeps;

4-equipment Inspection to program checkout/IFCC – control module the condition that may cause report program inspection or IFCC detected.The mistake that belongs to this type of comprises following error type: indication transmission command IU (for example arrives with the state damaging, TCCB completeness error), for data writing, invalid CRC detected, and for logical path and device address receive not the 2nd I/O operation of demand operating.

5-equipment Inspection to Cheng Xu inspection look into – control module mistake detected in the content of TCH

In one embodiment, Status Flag 1 field 336 comprises that incorrect length (IL) indicates 338.When passage and control module support DCW incorrect length function, position 0 is Il sign, when being set as 1, should indicating the DCW incorrect length condition of being indicated by DCW skew to cause stopping TCW I/O and operate.If DCW data counts not matching unit for writing the required data volume of DCW, if or DCW count the data volume that can be used for reading DCW on matching unit not, control module 118 detects incorrect length.

In one embodiment, if DCW202 comprises SLI sign 214, only when SLI sign 214 is 0 and when equipment state comprises the channel end condition of carrying device inspection state not, IL indicates that 338 are just set as 1.When IL sign 338 is set as 1 in transmission response IU, the DCW that DCW skew identification comprises incorrect length condition, and DCW residual count designation data transmission quantity, if had, transmit these volumes of transmitted data for incorrect length DCW.For the data transmission (if there is) that is arranged in the DCW before the incorrect length DCW of TCA, should complete, and should carry out for all crc checks of transmitted data, as described below.

When the DCW that comprises incorrect length condition is when reading DCW, in TCW I/O operating period, for all reading out datas that are transferred to passage, last transmission data I U is sent to passage INCLUDES CRC.If write before incorrect length that DCW is arranged in TCA reads DCW, the data that write DCW for these should controlled unit receive and should carry out crc check for data.The data that write DCW that read DCW immediately following incorrect length in TCA should be transferred to control module as required to obtain the CRC of data writing and to carry out crc check.

Incorrect length condition is not asked order, transmission CRC bias order or TTE command recognition, and no matter whether passage and control module support incorrect length function.

Transmission response IU330 can also comprise data length residual count (DLRC) field 340.For write operation and bidirectional operation, DL residual count be 32 without symbol bigit, the DL field in this integer given transmission order IU is poor with the actual byte number receiving from passage.For read operation, DL residual count be 32 without symbol bigit, the DL field in this integer given transmission order IU and the actual byte number that sends to passage poor.

For bidirectional operation, BRDL residual count field 342 is also included in transmission response IU300.For bidirectional operation, BRDL residual count be 32 without symbol bigit, the BRDL field in this integer given transmission order IU and the actual byte number that sends to passage poor.

Status Flag 3 fields 344 can the information of controlled unit 118 for providing relevant associated transmission mode to operate.This field can comprise that extended mode sends (ESS) position and comprises that with indication the extended mode of possible detection data sends by transmission response IU.This extended mode comprises extended mode (ES) sign, and these signs comprise the field such as ES type codes field.Type codes comprises I/O state (effective done state of extended mode district inclusion transmission mode I/O operation), I/O abnormal (information that the relevant transmission mode I/O operation being caused by exception condition of extended mode district inclusion stops), and inquiry state (state of extended mode district inclusion demand operating).

ES type codes in ES sign is I/O when abnormal, and ES comprises reason-code (RC).Exemplary reason-code comprises:

1-TCCB completeness error: control module determines that TCCB arrives (providing when exception code 4 is indicated in Status Flag 1 field) with the state damaging;

2-detects invalid CRC: invalid CRC(in the data that received, detected provides when exception code 4 is indicated in Status Flag 1 field);

The incorrect TCCB length of 3-is provided by (when exception code 5 is indicated in Status Flag 1 field, providing);

4-TCAH specify error (providing when exception code 5 is indicated in Status Flag 1 field);

5-DCW specify error: have mistake, wherein the DCW offset field of DCW in extended mode is provided by (providing when exception code 5 is indicated in Status Flag 1 field);

6-transmission direction specify error: the specified order specify data transfer direction of DCW of the DCW skew appointment in extended mode, this direction is different from the transmission direction of appointment in TCH, or R position and W position in TCH, be all set as 1 and control module bidirectional data transfers (providing when exception code 5 is indicated in Status Flag 1 field) is not provided;

7-transmission counting specify error (providing when exception code 5 is indicated in Status Flag 1 field);

Two I/O of 8-operation is in active state: although I/O operates on equipment in active state, the second non-inquiry TCCB has been transferred to equipment and has carried out.RCQ field is meaningless.This reason-code when indicating in Status Flag 1 field, exception code 4 is provided.

In the middle of one or more entry indications in 9-CRC offset blocks, CRC be not suitable on the position of equipment and/or when exception code 4 is indicated in Status Flag 1 field, providing the order of carrying out.

Extended mode can also provide reason-code qualifier (RCQ), and this qualifier provides the out of Memory of relevant I/O abnormal cause.Different reason-code qualifier types can be used for different type of errors, for example TCCB completeness error, output data crc error, the appointment of incorrect TCCB length, TCAH specify error and DCW specify error.The exemplary RCQ of TCCB completeness error comprises:

0-is without other message;

L1 field in the TCH of 1-data counts mistake-be not equal to for the data volume of the transmission command IU transmission control module of not supporting bidirectional operation adds the data volume of 8 appointments, or the L1 field that is not equal to the control module of not supporting bidirectional operation adds the data volume of 8 or 9 appointments; And

LRC on 2LRC mistake-transmission command IU is invalid.

The exemplary RCQ of DCW appointment comprises:

1-reserved field specify error: the reserved field comprising in 0 required DCW comprises nonzero value;

2-attribute field chaining command specify error: chaining command position is 1, and the skew of next DCW makes the part or all of expansion of next DCW surpass the end of TCA, or chaining command position is that 0 and 3 above unused bytes is retained in TCA;

3-controls data counts specify error: CD counting is specified the control data of the end that surpasses TCA;

4-TCOB DCW positional fault: a TCOB DCW is not the DCW in TCA;

5-TCOB DCW copy error: specify more than 1 TCOB DCW in TCA;

6-TCOB DCW counts specify error more: CD counting and DCW data counts are 0 or non-zero;

7-TCOB DCW anisotropy: TCOB DCW specifies in TCA, and the W position in TCH is 0;

8-TCOB DCW chain error: the chain command bit in TCOB DCW is 0, that is, TCOBDCW is the DCW in TCA;

9-TCOB counts specify error: TCOB DCW has the CD counting of non-zero or is not the data counts of 4 multiple;

10-TTE DCW positional fault: do not specify TCOB DCW and run into the TTE DCW that is not the DCW in TCA, or specified TCOB DCW, and run into the TTE DCW that is not the 2nd DCW in TCA;

11-TTE DCW copy error: run in TCA more than 1 TTE DCW;

12-TTE DCW CD counts specify error: the control data counts appointment in TTE DCW is not 0 value;

13-TTE DCW data counts specify error: data counts in TTE DCW is specified and is less than 8 or be not the value of 4 multiple;

14-TTE DCW anisotropy: specifying the W position in TTE DCW and TCH is 0;

15-TTE DCW chain error: the chain command bit in TTE DCW is 0; And

16-TCAX specify error: it is true specifying TTE DCW and following any one:

The length of TCA is 58 words or still less, or

The length of TCA is 59 words, and last the DCW specified control data in TCA and the control data length that surpasses 59 words through expansion, or

The maximum length of TCA is the first character that the last character in 60 words and TCA comprises DCW.

The exemplary RCQ of transmission direction specify error comprises:

It is 0 that 1-read direction specify error: DCW specifies the R position in input operation and TCH;

The W position that 2-writes in Inbound specify error: DCW appointment output function and TCH is 0.When note-W position in specifying TCOB or TTE DCW and TCH is 0, identification DCW specifies;

3-reads-writes conflict: the R position in TCH and W position be 1 and control module do not support bidirectional operation, or but control module supports bidirectional operation transmission command IU not comprise BRDL field, or R position and W position are not all 1, but transmission command IU comprises BRDL field;

The exemplary RCQ of transmission counting specify error comprises:

1-reads counting specify error: for read operation, the value of the DL field appointment in TCCB is not equal to the total data byte count that DCW in TCA adds byte of padding and CRC appointment; For bidirectional operation, the value of the BRDL field appointment in TCCB is not equal to the total data byte count that DCW adds byte of padding and CRC appointment that reads in TCA.

2-writes counting specify error: the value of the DL field appointment in TCCB be not equal to DCW in TCA add in the middle of the total data byte count of byte of padding, middle CRC, final byte of padding and final CRC byte appointment, if the first transmission data I U of data writing transmission comprises COB, counting comprises COB, any COB byte of padding and COB CRC byte.If TCA comprises TTEDCW, counting also comprises TCAX and TCAX CRC byte.

When channel subsystem detects design mistake, executive routine inspection.For transmission mode operation, design mistake also can be detected and be reported as program checkout by I/O equipment 116.Program checkout condition may be to be caused by following arbitrary reason:

Invalid TCW specifies: when following arbitrary condition being detected, identify invalid TCW and specify:

Reserved field for 0 inspection in 1.TCW does not comprise 0.

2. nonzero value is specified in TCW format fields.

Reading position and writing a position 10 that is 1, TCW attribute field in 3.TCW is 0, and the equipment of FCX bidirectional data transmission function or appointment of not installing is not supported bidirectional data transfers.

4.TCW the position 10 in attribute field be 0 and TCW in the length of TCCB length field appointment be less than 12 or be greater than 244.

Position 10 in 5.TCW attribute field be 1 and write operation (W) position of TCW be that read operation (R) position of 0, TCW is 0, or both are 0.

6.TCW the position 10 in attribute field be 1 and the subchannel of appointment not associated with the control module that is configured to Transmission Fibers passage services request.

When using TTE DCW, the program checkout that identification equipment detects during arbitrary condition below existing:

1. when not specifying TCOB DCW, TTE DCW is not the DCW in TCA.When specifying TCOB DCW, TTE DCW is not the 2nd DCW in TCA.

2. specify TTE DCW and do not specify write operation (that is, the W position in TCW is 0).

Chain order in 3.TTE DCW is 0.

4. specify an above TTE DCW.

Control data count field in 5.TTE DCW does not comprise 0.

6. count area comprises and is less than 8 value or is not the value of 4 multiple.

7. for TCA, following any one is very:

TCA does not comprise the DCW that at least one is not transmission command DCW.

It is not that chain order in the DCW of transmission command DCW and last DCW of TCA is masked as 0 that TCA comprises one or more.

When using TTE DCW and other TCMI and/or output data immediately following TCAX, the following should be for very; Otherwise the program checkout can identification equipment detecting:

Output in TCW-TIDA sign (zone bit 7) is necessary for 1; Or

When TIDAW is used for transmitting TCAX and when transmitting data, insert CBC control must or only for transmitting last TIDAW of TCAX, be made as 1.When TIDAW is only when transmitting TCAX, need not or only in the end set in a TIDAW and insert CBC.

During processing TCA, below detecting, during arbitrary condition, can identify TCCB content false:

1. the TCOB DCW that run into is not the DCW in TCA;

2. in TCA, run into the 2nd TCOB DCW;

3., when the W position in TCAH is 0, in TCA, run into TCOB DCW;

4.TCOB DCW does not set chain logo;

5. run into TCOB DCW, wherein CD counting and data counts are 0;

6. run into TCOB DCW, wherein CD counting and data counts are nonzero value;

7. run into TCOB DCW, wherein CD is counted as 0, and data counts is not 4 multiple;

8. run into TCOB DCW, wherein data counts is that 0, CD counting is not 4 multiple;

9. not specifying TCOB DCW and TTE DCW is not the DCW in TCA, or to specify TCOB and TTE DCW be not the 2nd DCW in TCA;

10., when the W position in TCAH is 0, in TCA, run into TTE DCW;

11.TTE DCW does not set chain logo;

12. run into the 2nd TTE DCW in TCA;

13. run into TTE DCW, and wherein CD is counted as nonzero value;

14. run into TTE DCW, and wherein data counts is 0 or is not 4 multiple;

15. to specify TTE DCW and following any one be true: the length of TCA is 58 words or still less; The length of TCA is 59 words, and last the DCW specified control data in TCA and control data length surpass 59 words through expansion; Or the maximum length of TCA is the first character that the last character in 60 words and TCA comprises DCW;

16.DCW comprise the order that need to control data, and CD count area is 0 or comprises appointment over the value of the data of the end of TCA;

The CD count area that 17.DCW comprises non-zero and order do not allow to provide control data;

18. during write operation, and equipment runs into the order of attempting carrying out reading out data transmission in TCA;

19. at during read operations, and equipment runs into the order of attempting carrying out data writing transmission in TCA;

20.CC position is that more than 0 and 3 untapped byte is retained in TCA in DCW;

21.CC position in DCW, be 1 and next DCW position be confirmed as being less than 8 bytes apart from the end of TCA, thereby but indication does not provide TCAX, or provides TCAX next DCW position to be confirmed as being less than 8 bytes apart from the end of TCAX;

22. for read operation or bidirectional operation, during reading DCW and become current DCW in TCA, data counts sum that reads DCW and current DCW before all adds that all byte of paddings and CRC byte surpass the DL field in TCCB, or, for bidirectional operation, surpass the BRDL field in TCCB;

23. for read operation or bidirectional operation, when last DCW in TCA becomes current DCW, the data counts sum of all DCW of reading adds that all byte of paddings and CRC byte are not equal to the DL field in TCCB, or, for bidirectional operation, be not equal to the BRDL field in TCCB;

24. for write operation or bidirectional operation, when the DCW in TCA becomes current DCW, the data counts sum of all DCW of writing adds that all byte of paddings and CRC byte (comprise all in the middle of byte of paddings and CRC byte) and COB byte, COB byte of padding and COB CRC byte (if transmission data I U comprises COB) and TCAX byte, TCAX byte of padding and TCAX CRC byte (if having TCAX) surpass the DL field in TCCB, or

25. for write operation or bidirectional operation, when last DCW in TCA becomes current DCW, the data counts sum of all DCW of writing adds that all byte of paddings and CRC byte (comprise all in the middle of byte of paddings and CRC byte) and COB byte, COB byte of padding and COBCRC byte (if transmission data I U comprises COB) and TCAX byte, TCAX byte of padding and TCAX CRC byte (if having TCAX) are not equal to the DL field in TCCB.

In one embodiment, before fill order pattern or transmission mode operation, set up the link between channel subsystem 114 and control module 118 and/or equipment 116.Each passage 128 having in the I/O system of physical connection with one or more control modules is called as " N_Port ", and it has unique identifier (" N_Port_ID ").Equally, each control module 118 also can be called as N_Port, the related N_Port_ID of its tool.Passage 128 and control module 118 can comprise respectively a plurality of channel image or control module image.Each N_Port comprises address designator, this identifier logon process initialization and the term of execution specify.Explicit N_Port login can be logined (PLOG) expansion link service execution by N_Port during initialization process.When N_Port is used another N_Port to carry out N_Port login, this N_Port is regarded as logining by other N_Port.

In one embodiment, the login of the link initialization use process between channel subsystem and control module (PRLI) expansion link service (ELS) is carried out.The general aspect of PRLI ELS (form that comprises PRLI ELS request and response) provides in FC-LS-2, wherein for defining in the specific settings of FC-SB-4 part below.

In PRLI process, support the passage 128 of PRLI, according to its configuration, request is sent to each control module 118, it configures also support process login ELS to determine whether control module 118 supports transmission mode operation.In one embodiment, PRLI asks, before setting up logical path, during passage initialization, to send, and the process that can be used as is published the result transmission of (PRLO).PRLI ELS for exchanging process login service parameter between passage 128 and control module 118.These parameters can ask to respond with PRLI by PRLI, between passage and control module, exchange.

PRLI request comprises service parameter page, wherein can comprise the type codes field (for example, being set as hex'1B' with indication SB-4 agreement) of identification FC-4 agreement.FC-SB-4 sign (for example, the byte 3 of the word 3 of PRLI requested page) comprises the one or more signs that the following describes:

0-supports transmission mode.When position 0 is set as 0, passage is not supported transmission mode operation.When position 0 is set as 1, passage is supported transmission mode operation.

1-retains.

2-supports DCW incorrect length (IL) function.For example, for example, when IL indicates in active state (, when position 2 is set as 1), passage 128 is supported DCW IL functions.When position 2 is set as 0, passage 128 is not supported DCW IL function.DCW IL function comprises supports sli (SLI) to indicate 214 and incorrect length sign 338.When supporting that the position (position 0) of transmission mode equals 0, position 2 should be set as 0.

5-supports bidirectional data transfers.For example, when bidirectional data transfers is indicated in active state (, position 5 is set as 1), passage 128 is supported bidirectional data transfers.When position 5 is set as 0, passage is not supported bidirectional data transfers.Only, when supporting that the position of transmission mode equals 1, this ability is meaningful.

7-supports the ready operation of forbidding the first transmission.When position 7 is set as 1, the ready operation of passage support forbidding the first transmission.When position 7 is set as 0, passage does not support to forbid the ready operation of the first transmission.When supporting that the position (position 0) of transmission mode equals 0, position 7 should be set as 0.

In one embodiment, PRLI response comprises that PRLI accepts service parameter page, (for example wherein can comprise the type codes field of identification FC-4 agreement, be set as hex'1B' with indication SB-4 agreement), FC-SB-4 sign (for example, the byte 3 of word 3) comprises the one or more defined sign the following describes:

0-supports transmission mode.When position 0 is set as 0, control module 118 is not supported transmission mode operation.When position 0 is set as 1, control module 118 is supported transmission mode operation.

2-supports DCW incorrect length (IL) function.When position 2 is set as 1, control module 118 is supported DCW IL function.When position 2 is set as 0, control module 118 is not supported DCW IL function.DCW incorrect length function comprises supports SLI sign 214 and incorrect length sign 338.When supporting that the position (position 0) of transmission mode equals 0, position 2 should be set as 0.

5-supports bidirectional data transfers.For example, when bidirectional data transfers is indicated in active state (, position 5 is set as 1), control module 118 is supported bidirectional data transfers.When position 5 is set as 0, control module 118 is not supported bidirectional data transfers.Only, when supporting that the position of transmission mode equals 1, this ability is meaningful.

7-supports the ready operation of forbidding the first transmission.When position 7 is set as 1, the ready operation of control module support forbidding the first transmission.When position 7 is set as 0, control module does not support to forbid the ready operation of the first transmission.When supporting that the position (position 0) of transmission mode equals 0, position 7 should be set as 0.

The technical effect of exemplary embodiment and advantage comprise except being arranged in the I/O order and equipment supported data of TCCB, transmission supported data and other command transfer can also be arrived to control module.Technical effect also comprises can continue to process DCW, no matter whether incorrect length condition detected, allows like this control module to continue to process I/O order, without stopping I/O operation.Other technical effect comprises and can, in single I/O operating period, transmit input and output data between passage and control module simultaneously.

Term used herein is just in order to describe specific embodiment and to be not intended to as restriction of the present invention.As used herein, singulative " ", " one " and " described " are intended to comprise equally plural form, unless context refers else clearly.Also will understand, when using in this instructions, root term " comprises " and/or " comprising " appointment exists feature, integer, step, operation, element and/or the assembly of statement, but does not get rid of the group that exists or increase one or more further features, integer, step, operation, element, assembly and/or their formations.

Below the counter structure in claim, material, operation and all devices or step and function element be equal to replacement, be intended to comprise any for other element with specifically noting in the claims combined carry out structure, material or the operation of this function.For example and illustration purpose, provided the description of this invention, but described description is not intended to be exhaustive or limit the invention to disclosed form.In the situation that not departing from scope and spirit of the present invention, for person of an ordinary skill in the technical field, many modifications and variations will be all apparent.The selection of embodiment and description are in order to explain best principle of the present invention and practical application, and when being suitable for conceived specific use, under making, other those of ordinary skill of technical field can be understood the various embodiment with various modifications of the present invention.

Person of ordinary skill in the field knows, various aspects of the present invention can be implemented as system, method or computer program.Therefore, various aspects of the present invention can specific implementation be following form, that is: hardware implementation mode, implement software mode (comprising firmware, resident software, microcode etc.) completely completely, or the embodiment of hardware and software aspect combination, can be referred to as " circuit ", " module " or " system " here.In addition, various aspects of the present invention can also be embodied as the form of the computer program in one or more computer-readable mediums, comprise computer-readable program code in this computer-readable medium.

Can adopt the combination in any of one or more computer-readable mediums.Computer-readable medium can be computer-readable signal media or computer-readable recording medium.Computer-readable recording medium can be for example-but be not limited to-electricity, magnetic, optical, electrical magnetic, infrared ray or semi-conductive system, device or device, or the combination of above-mentioned any appropriate.The example more specifically of computer-readable recording medium (non exhaustive list) comprising: have the electrical connection, portable computer diskette, hard disk, random-access memory (ram), ROM (read-only memory) (ROM), erasable type programmable read only memory (EPROM or flash memory), optical fiber, Portable, compact dish ROM (read-only memory) (CD-ROM), light storage device, magnetic memory device of one or more wires or the combination of above-mentioned any appropriate.In presents, computer-readable recording medium can be any comprising or stored program tangible medium, and this program can be used or be combined with it by instruction execution system, device or device.

Computer-readable signal media for example can comprise in base band or the data-signal of propagating as a carrier wave part, has wherein carried computer-readable program code.The data-signal of this propagation can adopt various ways, comprise-but the combination of be not limited to-electromagnetic signal, light signal or above-mentioned any appropriate.Computer-readable signal media can be any computer-readable medium beyond computer-readable recording medium, and this computer-readable medium can send, propagates or transmit the program for being used or be combined with it by instruction execution system, device or device.

The program code comprising on computer-readable medium can comprise with any suitable medium transmission-but be not limited to-wireless, wired, optical cable, RF etc., or the combination of above-mentioned any appropriate.

Can write for carrying out the computer program code of the operation of various aspects of the present invention with the combination in any of one or more programming languages, described programming language comprises object-oriented programming language-such as Java, Smalltalk, C++ etc., also comprises conventional process type programming language-such as " C " language or similar programming language.Program code can fully be carried out, partly on subscriber computer, carries out, as an independently software package execution, part part on subscriber computer, carry out or on remote computer or server, carry out completely on remote computer on subscriber computer.In relating to the situation of remote computer, remote computer can be by any kind network-comprise Local Area Network or wide area network (WAN)-be connected to subscriber computer, or, can be connected to outer computer (for example utilizing ISP to pass through Internet connection).

Below with reference to describing various aspects of the present invention according to the process flow diagram of the method for the embodiment of the present invention, device (system) and computer program and/or block diagram.Should be appreciated that the combination of each square frame in each square frame of process flow diagram and/or block diagram and process flow diagram and/or block diagram, can be realized by computer program instructions.These computer program instructions can offer the processor of multi-purpose computer, special purpose computer or other programmable data treating apparatus, thereby produce a kind of machine, make these instructions when the processor by computing machine or other programmable data treating apparatus is carried out, produced the device of the function/action of stipulating in the one or more square frames in realization flow figure and/or block diagram.

Also these computer program instructions can be stored in computer-readable medium, these instructions make computing machine, other programmable data treating apparatus or miscellaneous equipment with ad hoc fashion work, thereby the instruction being stored in computer-readable medium just produces the manufacture (article of manufacture) of the instruction of the function/action of stipulating in the one or more square frames that comprise in realization flow figure and/or block diagram.

Also computer program instructions can be loaded on computing machine, other programmable data treating apparatus or miscellaneous equipment, make to carry out sequence of operations step on computing machine, other programmable device or miscellaneous equipment, to produce computer implemented process, thereby the instruction that makes to carry out on computing machine or other programmable device provides the process of the function/action of stipulating in the one or more square frames in realization flow figure and/or block diagram.

At the process flow diagram shown in this, it is an example.Can there are many variations and not depart from spirit of the present invention in these figure described here or step (or operation).For example, can be by different order execution step, or can add, deletion or modify steps.All these variations are all regarded as a claimed part of the present invention.

Although described the preferred embodiments of the present invention, person of ordinary skill in the field will be appreciated that can be below the present and the future carries out various belonging to improvement and the enhancing of claim scope.These claims should be interpreted as safeguarding the of the present invention correct protection of describing first.

Claims (25)

1. one kind for the computer program being configured to carry out on the host computer system of communicating by letter with control module the I/O operation of I/O (I/O) operation start instruction, described control module and one or more devices communicating, described computer program comprises:

Tangible storage medium, it can read and store the instruction of being carried out a kind of method by described treatment circuit by processed circuit, and described method comprises:

By the channel subsystem of described host computer system, produce the command messages of at least one assigned I/O operation, described at least one command messages comprises one or more unit command words (DCW), each DCW and I/O order association, at least one DCW in wherein said one or more DCW comprises data counts and suppresses Length Indication (SLI), whether described SLI is configured to indicate described control module to continue in response to described control module detects incorrect length condition, to continue to carry out described I/O operation, described incorrect length conditional response does not mate and is detected in the described data counts data volume required with carrying out described I/O operational order, wherein required data be on described control module, can be used for the data of read operation order and described control module need to be for one of data of write operation order,

Described at least one command messages is forwarded to described control module;

From described control module, receive incorrect length (IL) value, in response to described SLI, be that a SLI value and described data counts do not mate with required data volume, described IL value is an IL value, in response to described SLI, be that the 2nd SLI value and described data counts do not mate with required data volume, described IL value is the 2nd IL value; And

In response to receive described IL value from described control module, IL indicator is stored in subchannel status word, described IL indicator represents described IL value.

2. according to the computer program of claim 1, wherein said at least one command messages comprises the TCCB that wherein comprises a plurality of DCW, and produces one or more positions of appointment the TCCB address field that described at least one command messages comprises the transmission command word (TCW) of storing in main system memory and collect TCCB.

3. according to the computer program of claim 1, wherein said at least one DCW comprises chaining command sign, it indicates follow-up DCW to be logically connected to described at least one DCW, and by described control module, is carried out after described control module is carried out described at least one DCW.

4. according to the computer program of claim 3, wherein said SLI indicates described control module continue chaining command and carry out described follow-up DCW in response to described control module detects described incorrect length condition.

5. according to the computer program of claim 1, wherein said SLI is the value in the SLI field in described at least one DCW, described value is that the described control module of 1 indication continues described I/O operation when described incorrect length condition being detected, and described value is that the described control module of 0 indication stops described I/O operation when described incorrect length condition being detected.

6. according to the computer program of claim 1, wherein said channel subsystem is configured to incorrect length condition be detected in response to described control module, and in response to described SLI, to be at least one data counts value in the data count field of described the first value and described at least one DCW need to, for writing that the data volume of DCW is not mated and described data counts value is not mated with the data volume that can be used for reading DCW on described equipment, receive described IL value with described equipment.

7. according to the computer program of claim 5, wherein said SLI field comprises value 1, and described at least one DCW reads DCW, and described computer program is configured to further execution:

Described in being used in response to chaining command sign directive command link, read DCW and described data counts value is greater than the amount of available data on described equipment, on described channel subsystem, receive from the described data volume in the data transmission of described control module, described data transmission comprises the one or more byte of paddings that are arranged in described data transmission, to equal described data counts value for the described data volume of described DCW transmission; Described in being not used in response to the link of described chaining command sign directive command, read DCW and described data counts value is greater than the amount of available data on described equipment, only receive described data volume or there is the data volume of one or more byte of paddings, to equal described data counts value for the described data volume of described DCW transmission; And

In response to described data counts value, be less than the amount of available data on described equipment, on described channel subsystem, receive the data volume that equals described data counts value.

8. according to the computer program of claim 5, wherein said SLI field comprises value 1, and described at least one DCW writes DCW, and described computer program is configured to further execution:

In response to the link of chaining command sign directive command, for said write DCW and described data counts value, be greater than the required data volume of described equipment, by described channel subsystem, the data volume that equals the required data volume of described equipment be transferred to described control module and abandon remaining data;

In response to the link of described chaining command sign directive command, be not used in said write DCW and described data counts value is greater than the required described data volume of described equipment, transmit the required described data volume of described equipment and transmit excessive data, until described data counts value runs out; And

In response to described data counts value, be less than the required described data volume of described equipment, the data volume that equals described count value is transferred to described control module.

9. according to the computer program of claim 1, wherein said at least one DCW comprises the SLI that contains SLI field, this SLI field is the 2nd SLI value and have value 1 in response to described SLI, in response to described SLI, it is a described SLI value and there is value 0, described channel subsystem is configured in response to carrying out or stop described I/O operation, the transmission response message that reception is returned from described control module, described transmission response message comprises the IL value that is arranged in incorrect length (IL) field, this field indicates whether to stop because of described incorrect length condition described I/O operation, in response to described SLI, be that a described SLI value and described data counts do not mate with required data volume, described IL field has value 1, in response to SLI described at least one, be that described the 2nd SLI value and data counts mate with required data volume, described IL field has value 0.

10. according to the computer program of claim 9, wherein said transmission response message comprises DCW offset field, and which in a plurality of DCW be this field indicate cause described incorrect length condition to be detected.

11. according to the computer program according to claim 1, and wherein said described channel subsystem is configured to carry out:

Process login (PRLI) request message is sent to described control module, described PRLI request message is configured to the link between channel subsystem and described control module described in initialization, described PRLI request message comprises head, and this has the value whether described channel subsystem of indication supports to use described SLI; And

From described control module, receive (PRLI) response message, described PRLI response message comprises head, and this has the value whether described control module of indication supports to use described SLI.

12. one kind for the device being configured to carry out on the host computer system of communicating by letter with control module the I/O operation that I/O (I/O) operational order initiates, described control module and one or more devices communicating, described host computer system is configured to carry out:

By the channel subsystem of described host computer system, produce the command messages of at least one assigned I/O operation, described at least one command messages comprises one or more unit command words (DCW), each DCW and I/O order association, at least one DCW in wherein said one or more DCW comprises data counts and suppresses Length Indication (SLI), whether described SLI is configured to indicate described control module to continue in response to described control module detects incorrect length condition, to continue to carry out described I/O operation, described incorrect length conditional response does not mate and is detected in the described data counts data volume required with carrying out described I/O operational order, wherein required data be on described control module, can be used for the data of read operation order and described control module need to be for one of data of write operation order,

Described at least one command messages is forwarded to described control module;

From described control module, receive incorrect length (IL) value, in response to described SLI, be that a SLI value and described data counts do not mate with required data volume, described IL value is an IL value, in response to described SLI, be that the 2nd SLI value and described data counts do not mate with required data volume, described IL value is the 2nd IL value; And

In response to receive described IL value from described control module, IL indicator is stored in subchannel status word, described IL indicator represents described IL value.

13. according to the device of claim 12, wherein said at least one DCW comprises chaining command sign, it indicates follow-up DCW to be logically connected to described at least one DCW, and after described control module is carried out described at least one DCW, by described control module, carried out, and described SLI indicates described control module continue chaining command and carry out described follow-up DCW in response to described control module detects described incorrect length condition.

14. according to the device of claim 12, wherein said SLI is the value in the SLI field in described at least one DCW, described value is that the described control module of 1 indication continues described I/O operation when described incorrect length condition being detected, and described value is that the described control module of 0 indication stops described I/O operation when described incorrect length condition being detected.

15. according to the device of claim 14, and wherein said SLI field comprises value 1, and described at least one DCW reads DCW, and described device is configured to carry out:

Described in being used in response to chaining command sign directive command link, read DCW and described data counts value is greater than the amount of available data on described equipment, on described channel subsystem, receive from the described data volume in the data transmission of described control module, described data transmission comprises the one or more byte of paddings that are arranged in described data transmission, to equal described data counts value for the described data volume of described DCW transmission;

Described in being not used in response to the link of described chaining command sign directive command, read DCW and described data counts value is greater than the amount of available data on described equipment, only receive described data volume or there is the data volume of one or more byte of paddings, to equal described data counts value for the described data volume of described DCW transmission; And

In response to described data counts value, be less than the amount of available data on described equipment, on described channel subsystem, receive the data volume that equals described data counts value.

16. according to the device of claim 14, and wherein said SLI field comprises value 1, and described at least one DCW writes DCW, and described device is configured to carry out:

In response to the link of chaining command sign directive command, for said write DCW and described data counts value, be greater than the required data volume of described equipment, by described channel subsystem, the data volume that equals the required data volume of described equipment be transferred to described control module and abandon remaining data;

In response to the link of described chaining command sign directive command, be not used in said write DCW and described data counts value is greater than the required described data volume of described equipment, transmit the required described data volume of described equipment and transmit excessive data, until described data counts value runs out; And

In response to described data counts value, be less than the required described data volume of described equipment, the data volume that equals described count value is transferred to described control module.

17. according to the device of claim 12, wherein said at least one DCW comprises the SLI that contains SLI field, this SLI field is the 2nd SLI value and have value 1 in response to described SLI, in response to described SLI, it is a described SLI value and there is value 0, described channel subsystem is configured in response to carrying out or stop described I/O operation, the transmission response message that reception is returned from described control module, described transmission response message comprises the IL value that is arranged in incorrect length (IL) field, this field indicates whether to stop because of described incorrect length condition described I/O operation, in response to described SLI, be that a described SLI value and described data counts do not mate with required data volume, described IL field has value 1, in response to SLI described at least one, be that described the 2nd SLI value and data counts mate with required data volume, described IL field has value 0.

18. according to the device of claim 17, and wherein said transmission response message comprises DCW offset field, and which in a plurality of DCW be this field indicate cause described incorrect length condition to be detected.

19. according to the device of claim 12, and wherein said described channel subsystem is configured to carry out:

Process login (PRLI) request message is sent to described control module, described PRLI request message is configured to the link between channel subsystem and described control module described in initialization, described PRLI request message comprises head, and this has the value whether described channel subsystem of indication supports to use described SLI; And

From described control module, receive (PRLI) response message, described PRLI response message comprises head, and this has the value whether described control module of indication supports to use described SLI.

20. 1 kinds for the method being configured to carry out on the host computer system of communicating by letter with control module the I/O operation that I/O (I/O) operational order initiates, described control module and one or more devices communicating, and described method comprises:

By the channel subsystem of described host computer system, produce the command messages of at least one assigned I/O operation, described at least one command messages comprises one or more unit command words (DCW), each DCW and I/O order association, at least one DCW in wherein said one or more DCW comprises data counts and suppresses Length Indication (SLI), whether described SLI is configured to indicate described control module to continue in response to described control module detects incorrect length condition, to continue to carry out described I/O operation, described incorrect length conditional response does not mate and is detected in the described data counts data volume required with carrying out described I/O operational order, wherein required data be on described control module, can be used for the data of read operation order and described control module need to be for one of data of write operation order,

Described at least one command messages is forwarded to described control module;

From described control module, receive incorrect length (IL) value, in response to described SLI, be that a SLI value and described data counts do not mate with required data volume, described IL value is an IL value, in response to described SLI, be that the 2nd SLI value and described data counts do not mate with required data volume, described IL value is the 2nd IL value; And

In response to receive described IL value from described control module, IL indicator is stored in subchannel status word, described IL indicator represents described IL value.

21. according to the method for claim 20, wherein said at least one DCW comprises chaining command sign, it indicates follow-up DCW to be logically connected to described at least one DCW, and after described control module is carried out described at least one DCW, by described control module, carried out, and described SLI indicates described control module continue chaining command and carry out described follow-up DCW in response to described control module detects described incorrect length condition.

22. according to the method for claim 20, wherein said SLI is the value in the SLI field in described at least one DCW, described value is that the described control module of 1 indication continues described I/O operation when described incorrect length condition being detected, and described value is that the described control module of 0 indication stops described I/O operation when described incorrect length condition being detected.

23. according to the method for claim 20, wherein said at least one DCW comprises the SLI that contains SLI field, this SLI field is the 2nd SLI value and have value 1 in response to described SLI, in response to described SLI, it is a described SLI value and there is value 0, described channel subsystem is configured in response to carrying out or stop described I/O operation, the transmission response message that reception is returned from described control module, described transmission response message comprises the IL value that is arranged in incorrect length (IL) field, this field indicates whether to stop because of described incorrect length condition described I/O operation, in response to described SLI, be that a described SLI value and described data counts do not mate with required data volume, described IL field has value 1, in response to SLI described at least one, be that described the 2nd SLI value and data counts mate with required data volume, described IL field has value 0.

24. according to the method for claim 23, and wherein said transmission response message comprises DCW offset field, and which in a plurality of DCW be this field indicate cause described incorrect length condition to be detected.

25. according to the method for claim 20, further comprises:

Process login (PRLI) request message is sent to described control module, described PRLI request message is configured to the link between channel subsystem and described control module described in initialization, described PRLI request message comprises head, and this has the value whether described channel subsystem of indication supports to use described SLI; And

From described control module, receive (PRLI) response message, described PRLI response message comprises head, and this has the value whether described control module of indication supports to use described SLI.

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